diff --git a/src/xpra/colorstreamhandler.py b/src/xpra/colorstreamhandler.py
index 41ac2e0d41..32e2951246 100644
--- a/src/xpra/colorstreamhandler.py
+++ b/src/xpra/colorstreamhandler.py
@@ -54,11 +54,8 @@ def _get_color(cls, level):
             return cls.DEBUG
         return cls.DEFAULT
 
-    def __init__(self, stream=None):
-        logging.StreamHandler.__init__(self, stream)
-
     def format(self, record):
-        text = logging.StreamHandler.format(self, record)
+        text = super().format(record)
         color = self._get_color(record.levelno)
         return color + text + self.DEFAULT
 
@@ -111,7 +108,7 @@ def _set_color(self, code):
         ctypes.windll.kernel32.SetConsoleTextAttribute(self._outhdl, code)      #@UndefinedVariable
 
     def __init__(self, stream=None):
-        logging.StreamHandler.__init__(self, stream)
+        super().__init__(stream)
         # get file handle for the stream
         import ctypes.util
         crtname = ctypes.util.find_msvcrt()
@@ -121,7 +118,7 @@ def __init__(self, stream=None):
     def emit(self, record):
         color = self._get_color(record.levelno)
         self._set_color(color)
-        logging.StreamHandler.emit(self, record)
+        super().emit(record)
         self._set_color(self.FOREGROUND_WHITE)
 
 # select ColorStreamHandler based on platform
diff --git a/src/xpra/log.py b/src/xpra/log.py
index f285d61f99..2f9909843f 100644
--- a/src/xpra/log.py
+++ b/src/xpra/log.py
@@ -411,7 +411,7 @@ def error(self, msg : str, *args, **kwargs):
 class CaptureHandler(logging.Handler):
 
     def __init__(self):
-        logging.Handler.__init__(self, logging.DEBUG)
+        super().__init__(logging.DEBUG)
         self.records = []
 
     def handle(self, record):
diff --git a/src/xpra/platform/darwin/gui.py b/src/xpra/platform/darwin/gui.py
index 6459beafa3..ab7fb10ffc 100644
--- a/src/xpra/platform/darwin/gui.py
+++ b/src/xpra/platform/darwin/gui.py
@@ -122,7 +122,7 @@ def do_ready():
 class OSX_Notifier(NotifierBase):
 
     def __init__(self, closed_cb=None, action_cb=None):
-        NotifierBase.__init__(self, closed_cb, action_cb)
+        super().__init__(closed_cb, action_cb)
         self.notifications = {}
         self.notification_center = NSUserNotificationCenter.defaultUserNotificationCenter()
         assert self.notification_center
diff --git a/src/xpra/platform/darwin/keyboard.py b/src/xpra/platform/darwin/keyboard.py
index 79d9d387e7..21207e584a 100644
--- a/src/xpra/platform/darwin/keyboard.py
+++ b/src/xpra/platform/darwin/keyboard.py
@@ -138,7 +138,7 @@ def get_keymap_modifiers(self):
         return  {}, [], ["lock", "control"]
 
     def set_modifier_mappings(self, mappings):
-        KeyboardBase.set_modifier_mappings(self, mappings)
+        super().set_modifier_mappings(mappings)
         self.meta_modifier = self.modifier_keys.get("Meta_L") or self.modifier_keys.get("Meta_R")
         self.control_modifier = self.modifier_keys.get("Control_L") or self.modifier_keys.get("Control_R") or "control"
         self.super_modifier = self.modifier_keys.get("Super_L") or self.modifier_keys.get("Super_R")
diff --git a/src/xpra/platform/darwin/osx_clipboard.py b/src/xpra/platform/darwin/osx_clipboard.py
index f586caea30..dee4dd4879 100644
--- a/src/xpra/platform/darwin/osx_clipboard.py
+++ b/src/xpra/platform/darwin/osx_clipboard.py
@@ -33,7 +33,7 @@ def __init__(self, *args, **kwargs):
             raise Exception("cannot load Pasteboard, maybe not running from a GUI session?")
         kwargs["clipboard.local"] = "CLIPBOARD"
         kwargs["clipboards.local"] = ["CLIPBOARD"]
-        ClipboardTimeoutHelper.__init__(self, *args, **kwargs)
+        super().__init__(*args, **kwargs)
 
 
     def __repr__(self):
@@ -57,7 +57,7 @@ def make_proxy(self, clipboard):
     def _munge_wire_selection_to_raw(self, encoding, dtype, dformat, data):
         if encoding=="atoms":
             return _filter_targets(data)
-        return ClipboardTimeoutHelper._munge_wire_selection_to_raw(self, encoding, dtype, dformat, data)
+        return super()._munge_wire_selection_to_raw(encoding, dtype, dformat, data)
 
 
 class OSXClipboardProxy(ClipboardProxyCore):
@@ -66,7 +66,7 @@ def __init__(self, selection, pasteboard, send_clipboard_request_handler, send_c
         self.pasteboard = pasteboard
         self.send_clipboard_request_handler = send_clipboard_request_handler
         self.send_clipboard_token_handler = send_clipboard_token_handler
-        ClipboardProxyCore.__init__(self, selection)
+        super().__init__(selection)
         self.update_change_count()
         #setup clipboard counter watcher:
         w = get_UI_watcher(GLib.timeout_add, GLib.source_remove)
diff --git a/src/xpra/platform/darwin/osx_menu.py b/src/xpra/platform/darwin/osx_menu.py
index b853c8b011..c726f6ef68 100644
--- a/src/xpra/platform/darwin/osx_menu.py
+++ b/src/xpra/platform/darwin/osx_menu.py
@@ -59,7 +59,7 @@ class OSXMenuHelper(GTKTrayMenuBase):
     """
 
     def __init__(self, client=None):
-        GTKTrayMenuBase.__init__(self, client)
+        super().__init__(client)
         log("OSXMenuHelper(%s)", client)
         self.menu_bar = None
         self.hidden_window = None
diff --git a/src/xpra/platform/darwin/osx_tray.py b/src/xpra/platform/darwin/osx_tray.py
index 0fc9a3ef2b..226bfc5b0e 100644
--- a/src/xpra/platform/darwin/osx_tray.py
+++ b/src/xpra/platform/darwin/osx_tray.py
@@ -22,7 +22,7 @@
 class OSXTray(TrayBase):
 
     def __init__(self, *args):
-        TrayBase.__init__(self, *args)
+        super().__init__(*args)
         from xpra.platform.darwin.gui import get_OSXApplication
         self.macapp = get_OSXApplication()
         assert self.macapp, "cannot use OSX Tray without the native gtkosx_application bindings"
diff --git a/src/xpra/platform/darwin/shadow_server.py b/src/xpra/platform/darwin/shadow_server.py
index 1ff84067eb..fd0e6a0bd5 100644
--- a/src/xpra/platform/darwin/shadow_server.py
+++ b/src/xpra/platform/darwin/shadow_server.py
@@ -144,12 +144,12 @@ def start_refresh(self, wid):
                 return
             log.warn("Warning: CGRegisterScreenRefreshCallback failed with error %i", err)
             log.warn(" using fallback timer method")
-        GTKShadowServerBase.start_refresh(self, wid)
+        super().start_refresh(wid)
 
     def stop_refresh(self, wid):
         log("stop_refresh(%i) mapped=%s, timer=%s", wid, self.mapped, self.refresh_timer)
         #may stop the timer fallback:
-        GTKShadowServerBase.stop_refresh(self, wid)
+        super().stop_refresh(wid)
         if self.refresh_registered and not self.mapped:
             try:
                 err = CG.CGUnregisterScreenRefreshCallback(self.screen_refresh_callback, None)
diff --git a/src/xpra/platform/win32/clipboard.py b/src/xpra/platform/win32/clipboard.py
index fe06f96a8e..53cbb8060a 100644
--- a/src/xpra/platform/win32/clipboard.py
+++ b/src/xpra/platform/win32/clipboard.py
@@ -62,7 +62,7 @@ class Win32Clipboard(ClipboardTimeoutHelper):
     """
     def __init__(self, send_packet_cb, progress_cb=None, **kwargs):
         self.init_window()
-        ClipboardTimeoutHelper.__init__(self, send_packet_cb, progress_cb, **kwargs)
+        super().__init__(send_packet_cb, progress_cb, **kwargs)
 
     def init_window(self):
         log("Win32Clipboard.init_window() creating clipboard window class and instance")
@@ -129,13 +129,13 @@ def make_proxy(self, selection):
     def _munge_wire_selection_to_raw(self, encoding, dtype, dformat, data):
         if encoding=="atoms":
             return _filter_targets(data)
-        return ClipboardTimeoutHelper._munge_wire_selection_to_raw(self, encoding, dtype, dformat, data)
+        return super()._munge_wire_selection_to_raw(encoding, dtype, dformat, data)
 
     def _munge_raw_selection_to_wire(self, target, dtype, dformat, data):
         if dtype=="ATOM":
             assert isinstance(data, (tuple, list))
             return "atoms", _filter_targets(data)
-        return ClipboardTimeoutHelper._munge_raw_selection_to_wire(self, target, dtype, dformat, data)
+        return super()._munge_raw_selection_to_wire(target, dtype, dformat, data)
 
 
 class Win32ClipboardProxy(ClipboardProxyCore):
@@ -143,7 +143,7 @@ def __init__(self, window, selection, send_clipboard_request_handler, send_clipb
         self.window = window
         self.send_clipboard_request_handler = send_clipboard_request_handler
         self.send_clipboard_token_handler = send_clipboard_token_handler
-        ClipboardProxyCore.__init__(self, selection)
+        super().__init__(selection)
 
     def set_want_targets(self, want_targets):
         self._want_targets = want_targets
diff --git a/src/xpra/platform/win32/keyboard.py b/src/xpra/platform/win32/keyboard.py
index 0b73d6e8d3..0cdaeb26ba 100644
--- a/src/xpra/platform/win32/keyboard.py
+++ b/src/xpra/platform/win32/keyboard.py
@@ -54,7 +54,7 @@ def __init__(self):
         KEY_TRANSLATIONS[("dead_grave", 65104,  55)]    = "grave"
 
     def set_modifier_mappings(self, mappings):
-        KeyboardBase.set_modifier_mappings(self, mappings)
+        super().set_modifier_mappings(mappings)
         self.num_lock_modifier = self.modifier_keys.get("Num_Lock")
         log("set_modifier_mappings found 'Num_Lock' with modifier value: %s", self.num_lock_modifier)
         for x in ("ISO_Level3_Shift", "Mode_switch"):
@@ -66,7 +66,7 @@ def set_modifier_mappings(self, mappings):
 
     def mask_to_names(self, mask):
         """ Patch NUMLOCK and AltGr """
-        names = KeyboardBase.mask_to_names(self, mask)
+        names = super().mask_to_names(mask)
         if EMULATE_ALTGR:
             rmenu = GetKeyState(win32con.VK_RMENU)
             #log("GetKeyState(VK_RMENU)=%s", rmenu)
@@ -207,7 +207,7 @@ def process_key_event(self, send_key_action_cb, wid, key_event):
                 key_event.keycode = -1
                 self.AltGr_modifiers(key_event.modifiers)
         self.send_delayed_key()
-        KeyboardBase.process_key_event(self, send_key_action_cb, wid, key_event)
+        super().process_key_event(send_key_action_cb, wid, key_event)
 
     def send_delayed_key(self):
         #timeout: this must be a real one, send it now
@@ -218,4 +218,4 @@ def send_delayed_key(self):
             rmenu = GetKeyState(win32con.VK_RMENU)
             log("send_delayed_key() GetKeyState(VK_RMENU)=%s", rmenu)
             if rmenu not in (0, 1):
-                KeyboardBase.process_key_event(self, *dk)
+                super().process_key_event(*dk)
diff --git a/src/xpra/platform/win32/namedpipes/connection.py b/src/xpra/platform/win32/namedpipes/connection.py
index 49abe51ee2..4bbc17d803 100644
--- a/src/xpra/platform/win32/namedpipes/connection.py
+++ b/src/xpra/platform/win32/namedpipes/connection.py
@@ -52,7 +52,7 @@
 class NamedPipeConnection(Connection):
     def __init__(self, name, pipe_handle, options):
         log("NamedPipeConnection(%s, %#x)", name, pipe_handle, options)
-        Connection.__init__(self, name, "named-pipe", options=options)
+        super().__init__(name, "named-pipe", options=options)
         self.pipe_handle = pipe_handle
         self.read_buffer = (c_char*BUFSIZE)()
         self.read_buffer_ptr = cast(addressof(self.read_buffer), c_void_p)
diff --git a/src/xpra/platform/win32/namedpipes/listener.py b/src/xpra/platform/win32/namedpipes/listener.py
index cec5aa862d..19c31d727b 100644
--- a/src/xpra/platform/win32/namedpipes/listener.py
+++ b/src/xpra/platform/win32/namedpipes/listener.py
@@ -80,7 +80,7 @@ def __init__(self, pipe_name, new_connection_cb=None):
         self.pipe_name = pipe_name
         self.new_connection_cb = new_connection_cb or self.new_connection
         self.exit_loop = False
-        Thread.__init__(self, name="NamedPipeListener-%s" % pipe_name)
+        super().__init__(name="NamedPipeListener-%s" % pipe_name)
         self.daemon = True
         self.security_attributes = None
         self.security_descriptor = None
diff --git a/src/xpra/platform/win32/shadow_server.py b/src/xpra/platform/win32/shadow_server.py
index 0a195ad427..2d095a5272 100644
--- a/src/xpra/platform/win32/shadow_server.py
+++ b/src/xpra/platform/win32/shadow_server.py
@@ -218,7 +218,7 @@ def init_capture(w, h, pixel_depth=32):
 class SeamlessRootWindowModel(RootWindowModel):
 
     def __init__(self, root, capture):
-        RootWindowModel.__init__(self, root, capture)
+        super().__init__(root, capture)
         log("SeamlessRootWindowModel(%s, %s) SEAMLESS=%s", root, capture, SEAMLESS)
         self.property_names.append("shape")
         self.dynamic_property_names.append("shape")
@@ -333,7 +333,7 @@ def get_property(self, prop):
             shape = {"Bounding.rectangles" : self.rectangles}
             #provide clip rectangle? (based on workspace area?)
             return shape
-        return RootWindowModel.get_property(self, prop)
+        return super().get_property(prop)
 
 
 class ShadowServer(GTKShadowServerBase):
diff --git a/src/xpra/platform/win32/win32_notifier.py b/src/xpra/platform/win32/win32_notifier.py
index e3937581e4..a32a7fec69 100644
--- a/src/xpra/platform/win32/win32_notifier.py
+++ b/src/xpra/platform/win32/win32_notifier.py
@@ -18,7 +18,7 @@
 class Win32_Notifier(NotifierBase):
 
     def __init__(self, *args):
-        NotifierBase.__init__(self, *args)
+        super().__init__(*args)
         self.handles_actions = GTK_Notifier is not None
         self.gtk_notifier = None
         self.gtk_notifications = set()
diff --git a/src/xpra/platform/win32/win32_tray.py b/src/xpra/platform/win32/win32_tray.py
index 3816cd7165..90e13e504c 100755
--- a/src/xpra/platform/win32/win32_tray.py
+++ b/src/xpra/platform/win32/win32_tray.py
@@ -25,7 +25,7 @@
 class Win32Tray(TrayBase):
 
     def __init__(self, *args):
-        TrayBase.__init__(self, *args)
+        super().__init__(*args)
         self.calculate_offset()
         self.default_icon_extension = "ico"
         icon_filename = get_icon_filename(self.default_icon_filename, "ico")
diff --git a/src/xpra/platform/xposix/appindicator_tray.py b/src/xpra/platform/xposix/appindicator_tray.py
index 4f887088c6..dd6491c65e 100644
--- a/src/xpra/platform/xposix/appindicator_tray.py
+++ b/src/xpra/platform/xposix/appindicator_tray.py
@@ -27,7 +27,7 @@
 DELETE_TEMP_FILE = envbool("XPRA_APPINDICATOR_DELETE_TEMP_FILE", True)
 
 gi.require_version('AppIndicator3', '0.1')
-from gi.repository import AppIndicator3, GdkPixbuf #pylint: disable=wrong-import-order
+from gi.repository import AppIndicator3, GdkPixbuf #pylint: disable=wrong-import-order, wrong-import-position, ungrouped-imports
 
 PASSIVE = AppIndicator3.IndicatorStatus.PASSIVE
 ACTIVE = AppIndicator3.IndicatorStatus.ACTIVE
@@ -39,7 +39,7 @@ def Indicator(tooltip, filename, status):
 class AppindicatorTray(TrayBase):
 
     def __init__(self, *args, **kwargs):
-        TrayBase.__init__(self, *args, **kwargs)
+        super().__init__(*args, **kwargs)
         filename = get_icon_filename(self.default_icon_filename) or "xpra.png"
         self._has_icon = False
         self.tmp_filename = None
diff --git a/src/xpra/scripts/config.py b/src/xpra/scripts/config.py
index 32c40ec81f..fd98695aac 100755
--- a/src/xpra/scripts/config.py
+++ b/src/xpra/scripts/config.py
@@ -33,7 +33,7 @@ class InitInfo(Exception):
 class InitExit(Exception):
     def __init__(self, status, msg):
         self.status = status
-        Exception.__init__(self, msg)
+        super().__init__(msg)
 
 
 DEBUG_CONFIG_PROPERTIES = os.environ.get("XPRA_DEBUG_CONFIG_PROPERTIES", "").split()
diff --git a/src/xpra/server/auth/env_auth.py b/src/xpra/server/auth/env_auth.py
index 09c7de07dd..1f53ee60fc 100644
--- a/src/xpra/server/auth/env_auth.py
+++ b/src/xpra/server/auth/env_auth.py
@@ -11,7 +11,7 @@ class Authenticator(SysAuthenticator):
 
     def __init__(self, username, **kwargs):
         self.var_name = kwargs.pop("name", "XPRA_PASSWORD")
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.authenticate = self.authenticate_hmac
 
     def __repr__(self):
diff --git a/src/xpra/server/auth/exec_auth.py b/src/xpra/server/auth/exec_auth.py
index c3c7de36cf..d5af2182b5 100644
--- a/src/xpra/server/auth/exec_auth.py
+++ b/src/xpra/server/auth/exec_auth.py
@@ -45,7 +45,7 @@ def __init__(self, username, **kwargs):
         log("exec connection info: %s", connection)
         assert connection, "connection object is missing"
         self.connection_str = str(connection)
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
 
     def requires_challenge(self) -> bool:
         return False
diff --git a/src/xpra/server/auth/file_auth_base.py b/src/xpra/server/auth/file_auth_base.py
index 069da83a26..371277d5d5 100644
--- a/src/xpra/server/auth/file_auth_base.py
+++ b/src/xpra/server/auth/file_auth_base.py
@@ -24,7 +24,7 @@ def __init__(self, username, **kwargs):
             exec_cwd = kwargs.get("exec_cwd", os.getcwd())
             password_file = os.path.join(exec_cwd, password_file)
         log("FileAuthenticatorBase filename=%s", password_file)
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.password_filename = password_file
         self.password_filedata = None
         self.password_filetime = None
diff --git a/src/xpra/server/auth/gss_auth.py b/src/xpra/server/auth/gss_auth.py
index a2c9ed6604..964e4c3322 100755
--- a/src/xpra/server/auth/gss_auth.py
+++ b/src/xpra/server/auth/gss_auth.py
@@ -19,7 +19,7 @@ def __init__(self, username, **kwargs):
         self.gid = parse_gid(kwargs.pop("gid", None))
         username = kwargs.pop("username", username)
         kwargs["prompt"] = kwargs.pop("prompt", "GSS token")
-        SysAuthenticatorBase.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         log("gss auth: service=%s, username=%s", self.service, username)
 
     def get_uid(self):
diff --git a/src/xpra/server/auth/hosts_auth.py b/src/xpra/server/auth/hosts_auth.py
index d712d22978..bce30a8def 100644
--- a/src/xpra/server/auth/hosts_auth.py
+++ b/src/xpra/server/auth/hosts_auth.py
@@ -57,7 +57,7 @@ def __init__(self, username, **kwargs):
             raise
         self.peername = peername
         self.host = host
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
 
     def requires_challenge(self) -> bool:
         return False
diff --git a/src/xpra/server/auth/kerberos_password_auth.py b/src/xpra/server/auth/kerberos_password_auth.py
index ecf313d8e4..e1c348574d 100755
--- a/src/xpra/server/auth/kerberos_password_auth.py
+++ b/src/xpra/server/auth/kerberos_password_auth.py
@@ -20,7 +20,7 @@ def __init__(self, username, **kwargs):
         self.uid = parse_uid(kwargs.pop("uid", None))
         self.gid = parse_gid(kwargs.pop("gid", None))
         username = kwargs.pop("username", username)
-        SysAuthenticatorBase.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         log("kerberos-password auth: service=%s, realm=%s, username=%s", self.service, self.realm, username)
 
     def get_uid(self):
@@ -36,7 +36,7 @@ def get_challenge(self, digests):
         if "xor" not in digests:
             log.error("Error: kerberos authentication requires the 'xor' digest")
             return None
-        return SysAuthenticatorBase.get_challenge(self, ["xor"])
+        return super().get_challenge(["xor"])
 
     def check(self, password) -> bool:
         try:
diff --git a/src/xpra/server/auth/kerberos_token_auth.py b/src/xpra/server/auth/kerberos_token_auth.py
index 0c2af6ac76..a7104d7ed8 100755
--- a/src/xpra/server/auth/kerberos_token_auth.py
+++ b/src/xpra/server/auth/kerberos_token_auth.py
@@ -20,7 +20,7 @@ def __init__(self, username, **kwargs):
         self.gid = parse_gid(kwargs.pop("gid", None))
         username = kwargs.pop("username", username)
         kwargs["prompt"] = kwargs.pop("prompt", "kerberos token")
-        SysAuthenticatorBase.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         log("kerberos-token auth: service=%s, username=%s", self.service, username)
 
     def get_uid(self):
diff --git a/src/xpra/server/auth/ldap3_auth.py b/src/xpra/server/auth/ldap3_auth.py
index 3b0baf0988..252803222b 100755
--- a/src/xpra/server/auth/ldap3_auth.py
+++ b/src/xpra/server/auth/ldap3_auth.py
@@ -38,7 +38,7 @@ def __init__(self, username, **kwargs):
         self.authentication = kwargs.pop("authentication", "NTLM").upper()
         assert self.authentication in ("SIMPLE", "SASL", "NTLM"), "invalid authentication mechanism '%s'" % self.authentication
         username = kwargs.pop("username", username)
-        SysAuthenticatorBase.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         log("ldap auth: host=%s, port=%i, tls=%s",
             self.host, self.port, self.tls)
 
@@ -55,7 +55,7 @@ def get_challenge(self, digests):
         if "xor" not in digests:
             log.error("Error: ldap authentication requires the 'xor' digest")
             return None
-        return SysAuthenticatorBase.get_challenge(self, ["xor"])
+        return super().get_challenge(["xor"])
 
     def check(self, password) -> bool:
         log("check(%s)", obsc(password))
diff --git a/src/xpra/server/auth/ldap_auth.py b/src/xpra/server/auth/ldap_auth.py
index c0a24527b9..5cb3567d5a 100755
--- a/src/xpra/server/auth/ldap_auth.py
+++ b/src/xpra/server/auth/ldap_auth.py
@@ -36,7 +36,7 @@ def __init__(self, username, **kwargs):
         self.port = int(kwargs.pop("port", default_port))
         self.username_format = kwargs.pop("username_format", "cn=%username, o=%domain")
         #self.username_format = kwargs.pop("username_format", "%username@%domain")
-        SysAuthenticatorBase.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         log("ldap auth: host=%s, port=%i, tls=%s, username_format=%s, cacert=%s, encoding=%s",
             self.host, self.port, self.tls, self.username_format, self.cacert, self.encoding)
 
@@ -53,7 +53,7 @@ def get_challenge(self, digests):
         if "xor" not in digests:
             log.error("Error: ldap authentication requires the 'xor' digest")
             return None
-        return SysAuthenticatorBase.get_challenge(self, ["xor"])
+        return super().get_challenge(["xor"])
 
     def check(self, password) -> bool:
         log("check(%s)", obsc(password))
diff --git a/src/xpra/server/auth/multifile_auth.py b/src/xpra/server/auth/multifile_auth.py
index b51446dae9..c8134c3103 100644
--- a/src/xpra/server/auth/multifile_auth.py
+++ b/src/xpra/server/auth/multifile_auth.py
@@ -40,7 +40,7 @@ def parse_auth_line(line):
 
 class Authenticator(FileAuthenticatorBase):
     def __init__(self, username, **kwargs):
-        FileAuthenticatorBase.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.sessions = None
 
     def parse_filedata(self, data):
diff --git a/src/xpra/server/auth/mysql_auth.py b/src/xpra/server/auth/mysql_auth.py
index 276065560d..06fe1b5f54 100755
--- a/src/xpra/server/auth/mysql_auth.py
+++ b/src/xpra/server/auth/mysql_auth.py
@@ -43,7 +43,7 @@ def db_from_uri(uri):
 class Authenticator(SQLAuthenticator):
 
     def __init__(self, username, uri, **kwargs):
-        SQLAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.uri = uri
 
     def db_cursor(self, *sqlargs):
@@ -62,7 +62,7 @@ def __repr__(self):
 class MySQLDatabaseUtil(DatabaseUtilBase):
 
     def __init__(self, uri):
-        DatabaseUtilBase.__init__(self, uri)
+        super().__init__(uri)
         import mysql.connector as mysql  #@UnresolvedImport
         assert mysql.paramstyle=="pyformat"
         self.param = "%s"
diff --git a/src/xpra/server/auth/none_auth.py b/src/xpra/server/auth/none_auth.py
index 75698e1c85..d3ab7198a0 100644
--- a/src/xpra/server/auth/none_auth.py
+++ b/src/xpra/server/auth/none_auth.py
@@ -10,7 +10,7 @@
 class Authenticator(SysAuthenticator):
 
     def __init__(self, username, **kwargs):
-        SysAuthenticator.__init__(self, username or get_username(), **kwargs)
+        super().__init__(username or get_username(), **kwargs)
         self.salt = None
 
     def requires_challenge(self):
diff --git a/src/xpra/server/auth/pam_auth.py b/src/xpra/server/auth/pam_auth.py
index acf5d4dc51..bad0d6ff9f 100644
--- a/src/xpra/server/auth/pam_auth.py
+++ b/src/xpra/server/auth/pam_auth.py
@@ -37,7 +37,7 @@ class Authenticator(SysAuthenticator):
     def __init__(self, username, **kwargs):
         self.service = kwargs.pop("service", PAM_AUTH_SERVICE)
         self.check_account = parse_bool("check-account", kwargs.pop("check-account", PAM_CHECK_ACCOUNT), False)
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
 
     def check(self, password) -> bool:
         log("pam.check(..) pw=%s", self.pw)
@@ -49,7 +49,7 @@ def get_challenge(self, digests):
         if "xor" not in digests:
             log.error("Error: pam authentication requires the 'xor' digest")
             return None
-        return SysAuthenticator.get_challenge(self, ["xor"])
+        return super().get_challenge(["xor"])
 
     def __repr__(self):
         return "PAM"
diff --git a/src/xpra/server/auth/password_auth.py b/src/xpra/server/auth/password_auth.py
index 8a24eadd3f..7f607c2a2c 100644
--- a/src/xpra/server/auth/password_auth.py
+++ b/src/xpra/server/auth/password_auth.py
@@ -10,7 +10,7 @@ class Authenticator(SysAuthenticator):
 
     def __init__(self, username, **kwargs):
         self.value = kwargs.pop("value", None)
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.authenticate = self.authenticate_hmac
 
     def __repr__(self):
diff --git a/src/xpra/server/auth/peercred_auth.py b/src/xpra/server/auth/peercred_auth.py
index fbbb4a969c..1649fa54db 100644
--- a/src/xpra/server/auth/peercred_auth.py
+++ b/src/xpra/server/auth/peercred_auth.py
@@ -77,7 +77,7 @@ def __init__(self, username, **kwargs):
         except Exception as e:
             log.error("Error: cannot get peer uid")
             log.error(" %s", e)
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
 
     def get_uid(self):
         return self.uid
diff --git a/src/xpra/server/auth/sql_auth.py b/src/xpra/server/auth/sql_auth.py
index 3e2474c3fc..558c9faa13 100755
--- a/src/xpra/server/auth/sql_auth.py
+++ b/src/xpra/server/auth/sql_auth.py
@@ -14,7 +14,7 @@
 class Authenticator(SQLAuthenticator):
 
     def __init__(self, username, uri, **kwargs):
-        SQLAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.uri = uri
 
     def db_cursor(self, *sqlargs):
@@ -34,7 +34,7 @@ def __repr__(self):
 class SQLDatabaseUtil(DatabaseUtilBase):
 
     def __init__(self, uri):
-        DatabaseUtilBase.__init__(self, uri)
+        super().__init__(uri)
         #from sqlalchemy import create_engine    #@UnresolvedImport
         #db = create_engine(self.uri)
         self.param = os.environ.get("PARAMSTYLE", "%s")
diff --git a/src/xpra/server/auth/sqlauthbase.py b/src/xpra/server/auth/sqlauthbase.py
index 6e1c5a693e..9a0450d2d9 100755
--- a/src/xpra/server/auth/sqlauthbase.py
+++ b/src/xpra/server/auth/sqlauthbase.py
@@ -16,7 +16,7 @@ def __init__(self, username, **kwargs):
         self.sessions_query = kwargs.pop("sessions_query",
                                          "SELECT uid, gid, displays, env_options, session_options "+
                                          "FROM users WHERE username=(%s) AND password=(%s)")
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.authenticate = self.authenticate_hmac
 
     def db_cursor(self, *sqlargs):
diff --git a/src/xpra/server/auth/sqlite_auth.py b/src/xpra/server/auth/sqlite_auth.py
index a7bdbadd09..7656f4f857 100755
--- a/src/xpra/server/auth/sqlite_auth.py
+++ b/src/xpra/server/auth/sqlite_auth.py
@@ -15,7 +15,7 @@
 class Authenticator(SQLAuthenticator):
 
     def __init__(self, username, filename="sqlite.sdb", **kwargs):
-        SQLAuthenticator.__init__(self, username)
+        super().__init__(username)
         if filename and not os.path.isabs(filename):
             exec_cwd = kwargs.get("exec_cwd", os.getcwd())
             filename = os.path.join(exec_cwd, filename)
@@ -65,7 +65,7 @@ def parse_session_data(self, data):
 class SqliteDatabaseUtil(DatabaseUtilBase):
 
     def __init__(self, uri):
-        DatabaseUtilBase.__init__(self, uri)
+        super().__init__(uri)
         import sqlite3
         assert sqlite3.paramstyle=="qmark"
         self.param = "?"
diff --git a/src/xpra/server/auth/sys_auth_base.py b/src/xpra/server/auth/sys_auth_base.py
index f8a8601b33..7ec6eb5af6 100644
--- a/src/xpra/server/auth/sys_auth_base.py
+++ b/src/xpra/server/auth/sys_auth_base.py
@@ -191,7 +191,7 @@ def get_sessions(self):
 class SysAuthenticator(SysAuthenticatorBase):
 
     def __init__(self, username, **kwargs):
-        SysAuthenticatorBase.__init__(self, username)
+        super().__init__(username)
         self.pw = None
         if POSIX:
             try:
diff --git a/src/xpra/server/auth/u2f_auth.py b/src/xpra/server/auth/u2f_auth.py
index 41af9320b1..ed0277d19d 100755
--- a/src/xpra/server/auth/u2f_auth.py
+++ b/src/xpra/server/auth/u2f_auth.py
@@ -28,7 +28,7 @@ class Authenticator(SysAuthenticator):
     def __init__(self, username, **kwargs):
         self.app_id = kwargs.pop("app_id", APP_ID)
         key_hexstring = kwargs.pop("public_key", "")
-        SysAuthenticator.__init__(self, username, **kwargs)
+        super().__init__(username, **kwargs)
         self.public_keys = {}
         key_strs = {}
         if key_hexstring:
diff --git a/src/xpra/server/auth/win32_auth.py b/src/xpra/server/auth/win32_auth.py
index 10ad0f3b78..6e40034e49 100644
--- a/src/xpra/server/auth/win32_auth.py
+++ b/src/xpra/server/auth/win32_auth.py
@@ -33,7 +33,7 @@ def get_gid(self):
     def get_challenge(self, digests):
         if "xor" not in digests:
             raise Exception("win32 authenticator requires the 'xor' digest")
-        return SysAuthenticator.get_challenge(self, ["xor"])
+        return super().get_challenge(["xor"])
 
     def check(self, password) -> bool:
         token = HANDLE()
diff --git a/src/xpra/server/background_worker.py b/src/xpra/server/background_worker.py
index b62a49d3da..2759db8fa6 100644
--- a/src/xpra/server/background_worker.py
+++ b/src/xpra/server/background_worker.py
@@ -20,7 +20,7 @@ class Worker_Thread(Thread):
     """
 
     def __init__(self):
-        Thread.__init__(self, name="Worker_Thread")
+        super().__init__(name="Worker_Thread")
         self.items = Queue()
         self.exit = False
         self.setDaemon(True)
diff --git a/src/xpra/server/dbus/dbus_server.py b/src/xpra/server/dbus/dbus_server.py
index dbf8856d58..513f92647d 100755
--- a/src/xpra/server/dbus/dbus_server.py
+++ b/src/xpra/server/dbus/dbus_server.py
@@ -43,7 +43,7 @@ def __init__(self, server=None, extra=""):
         name = BUS_NAME
         if extra:
             name += extra.replace(".", "_").replace(":", "_")
-        DBUS_Server_Base.__init__(self, bus, server, name)
+        super().__init__(bus, server, name)
         self._properties.update({
             "idle-timeout"          : ("idle_timeout",          ni),
             "server-idle-timeout"   : ("server_idle_timeout",   ni),
diff --git a/src/xpra/server/dbus/dbus_server_base.py b/src/xpra/server/dbus/dbus_server_base.py
index 3906b2e216..4e8e5d538a 100755
--- a/src/xpra/server/dbus/dbus_server_base.py
+++ b/src/xpra/server/dbus/dbus_server_base.py
@@ -19,7 +19,7 @@ class DBUS_Server_Base(dbus.service.Object):
     def __init__(self, bus, server, name):
         self.server = server
         bus_name = dbus.service.BusName(name, bus)
-        dbus.service.Object.__init__(self, bus_name, PATH)
+        super().__init__(bus_name, PATH)
         self.log("(%s)", server)
         self._properties = {}
 
diff --git a/src/xpra/server/dbus/dbus_source.py b/src/xpra/server/dbus/dbus_source.py
index 078059ded9..afd5bf6456 100755
--- a/src/xpra/server/dbus/dbus_source.py
+++ b/src/xpra/server/dbus/dbus_source.py
@@ -40,7 +40,7 @@ def __init__(self, source=None, extra=""):
         if extra:
             name += extra.replace(".", "_").replace(":", "_")
         bus_name = dbus.service.BusName(name, session_bus)
-        dbus.service.Object.__init__(self, bus_name, self.path)
+        super().__init__(bus_name, self.path)
         self.log("(%s)", source)
         self._properties = {"bell"              : ("send_bell",             ni),
                             "cursors"           : ("send_cursors",          ni),
diff --git a/src/xpra/server/gtk_server_base.py b/src/xpra/server/gtk_server_base.py
index 7caf635594..8d4f928e34 100644
--- a/src/xpra/server/gtk_server_base.py
+++ b/src/xpra/server/gtk_server_base.py
@@ -115,7 +115,7 @@ def do_run(self):
 
 
     def make_hello(self, source):
-        capabilities = ServerBase.make_hello(self, source)
+        capabilities = super().make_hello(source)
         if source.wants_display:
             display = Gdk.Display.get_default()
             max_size = tuple(display.get_maximal_cursor_size())
@@ -129,7 +129,7 @@ def make_hello(self, source):
         return capabilities
 
     def get_ui_info(self, proto, *args):
-        info = ServerBase.get_ui_info(self, proto, *args)
+        info = super().get_ui_info(proto, *args)
         info.setdefault("server", {}).update({
                                               "display"             : Gdk.Display.get_default().get_name(),
                                               "root_window_size"    : self.get_root_window_size(),
@@ -185,7 +185,7 @@ def get_ui_cursor_info(self):
 
     def do_get_info(self, proto, *args):
         start = monotonic_time()
-        info = ServerBase.do_get_info(self, proto, *args)
+        info = super().do_get_info(proto, *args)
         vi = get_gtk_version_info()
         vi["type"] = "Python/gtk"
         info.setdefault("server", {}).update(vi)
diff --git a/src/xpra/server/http_handler.py b/src/xpra/server/http_handler.py
index 09ec11a7ee..f856d2fadc 100644
--- a/src/xpra/server/http_handler.py
+++ b/src/xpra/server/http_handler.py
@@ -51,7 +51,7 @@ def __init__(self, sock, addr,
         server = AdHocStruct()
         server.logger = log
         self.directory_listing = DIRECTORY_LISTING
-        BaseHTTPRequestHandler.__init__(self, sock, addr, server)
+        super().__init__(sock, addr, server)
 
     def translate_path(self, path):
         #code duplicated from superclass since we can't easily inject the web_root..
diff --git a/src/xpra/server/proxy/proxy_dbus_server.py b/src/xpra/server/proxy/proxy_dbus_server.py
index 6e32fcae66..b6a167b7a1 100755
--- a/src/xpra/server/proxy/proxy_dbus_server.py
+++ b/src/xpra/server/proxy/proxy_dbus_server.py
@@ -23,7 +23,7 @@ def __init__(self, server=None):
             bus = init_system_bus()
         else:
             bus = init_session_bus()
-        DBUS_Server_Base.__init__(self, bus, server, BUS_NAME)
+        super().__init__(bus, server, BUS_NAME)
 
     @dbus.service.method(INTERFACE, in_signature='', out_signature='a{sv}')
     def GetInfo(self):
diff --git a/src/xpra/server/proxy/proxy_instance_thread.py b/src/xpra/server/proxy/proxy_instance_thread.py
index 582b8e38a0..ebdeb00c28 100644
--- a/src/xpra/server/proxy/proxy_instance_thread.py
+++ b/src/xpra/server/proxy/proxy_instance_thread.py
@@ -19,9 +19,9 @@ def __init__(self, session_options,
                  video_encoders, pings,
                  client_proto, server_conn,
                  disp_desc, cipher, encryption_key, caps):
-        ProxyInstance.__init__(self, session_options,
-                               video_encoders, pings,
-                               disp_desc, cipher, encryption_key, caps)
+        super().__init__(session_options,
+                         video_encoders, pings,
+                         disp_desc, cipher, encryption_key, caps)
         self.client_protocol = client_proto
         self.server_conn = server_conn
 
diff --git a/src/xpra/server/proxy/proxy_server.py b/src/xpra/server/proxy/proxy_server.py
index 3c2b54398b..8eef637d3b 100644
--- a/src/xpra/server/proxy/proxy_server.py
+++ b/src/xpra/server/proxy/proxy_server.py
@@ -197,7 +197,7 @@ def verify_connection_accepted(self, protocol):
             self.send_disconnect(protocol, LOGIN_TIMEOUT)
 
     def hello_oked(self, proto, packet, c, auth_caps):
-        if ServerCore.hello_oked(self, proto, packet, c, auth_caps):
+        if super().hello_oked(proto, packet, c, auth_caps):
             #already handled in superclass
             return
         self.accept_client(proto, c)
diff --git a/src/xpra/server/window/window_source.py b/src/xpra/server/window/window_source.py
index bd1d182ba6..1920f014c1 100644
--- a/src/xpra/server/window/window_source.py
+++ b/src/xpra/server/window/window_source.py
@@ -133,7 +133,7 @@ def __init__(self,
                     rgb_formats,
                     default_encoding_options,
                     mmap, mmap_size, bandwidth_limit, jitter):
-        WindowIconSource.__init__(self, window_icon_encodings, icons_encoding_options)
+        super().__init__(window_icon_encodings, icons_encoding_options)
         self.idle_add = idle_add
         self.timeout_add = timeout_add
         self.source_remove = source_remove
diff --git a/src/xpra/server/window/window_video_source.py b/src/xpra/server/window/window_video_source.py
index 0e4b30dd81..7354f20cba 100644
--- a/src/xpra/server/window/window_video_source.py
+++ b/src/xpra/server/window/window_video_source.py
@@ -105,7 +105,7 @@ def __init__(self, *args):
         #this will call init_vars():
         self.supports_scrolling = False
         self.video_subregion = None
-        WindowSource.__init__(self, *args)
+        super().__init__(*args)
         self.supports_eos = self.encoding_options.boolget("eos")
         self.scroll_encoding = SCROLL_ENCODING
         self.supports_scrolling = self.scroll_encoding and self.encoding_options.boolget("scrolling") and not STRICT_MODE
@@ -169,7 +169,7 @@ def init_vars(self):
         self.last_scroll_time = 0
 
     def do_set_auto_refresh_delay(self, min_delay, delay):
-        WindowSource.do_set_auto_refresh_delay(self, min_delay, delay)
+        super().do_set_auto_refresh_delay(min_delay, delay)
         r = self.video_subregion
         if r:
             r.set_auto_refresh_delay(self.base_auto_refresh_delay)
@@ -349,7 +349,7 @@ def set_new_encoding(self, encoding, strict=None):
         if self.encoding!=encoding:
             #ensure we re-init the codecs asap:
             self.cleanup_codecs()
-        WindowSource.set_new_encoding(self, encoding, strict)
+        super().set_new_encoding(encoding, strict)
 
     def update_encoding_selection(self, encoding=None, exclude=None, init=False):
         #override so we don't use encodings that don't have valid csc modes:
@@ -371,7 +371,7 @@ def update_encoding_selection(self, encoding=None, exclude=None, init=False):
         self.common_video_encodings = [x for x in PREFERED_ENCODING_ORDER if x in self.video_encodings and x in self.core_encodings]
         log("update_encoding_options: common_video_encodings=%s, csc_encoder=%s, video_encoder=%s",
             self.common_video_encodings, self._csc_encoder, self._video_encoder)
-        WindowSource.update_encoding_selection(self, encoding, exclude, init)
+        super().update_encoding_selection(encoding, exclude, init)
 
     def do_set_client_properties(self, properties):
         #client may restrict csc modes for specific windows
@@ -380,7 +380,7 @@ def do_set_client_properties(self, properties):
         self.video_subregion.supported = properties.boolget("encoding.video_subregion", VIDEO_SUBREGION) and VIDEO_SUBREGION
         if properties.get("scaling.control") is not None:
             self.scaling_control = max(0, min(100, properties.intget("scaling.control", 0)))
-        WindowSource.do_set_client_properties(self, properties)
+        super().do_set_client_properties(properties)
         #encodings may have changed, so redo this:
         nv_common = (set(self.server_core_encodings) & set(self.core_encodings)) - set(self.video_encodings)
         self.non_video_encodings = [x for x in PREFERED_ENCODING_ORDER if x in nv_common]
@@ -539,7 +539,7 @@ def do_damage(self, ww, wh, x, y, w, h, options):
             if r and r.intersects(x, y, w, h):
                 #the damage will take care of scheduling it again
                 vs.cancel_refresh_timer()
-        WindowSource.do_damage(self, ww, wh, x, y, w, h, options)
+        super().do_damage(ww, wh, x, y, w, h, options)
 
 
     def cancel_damage(self):
@@ -570,16 +570,16 @@ def full_quality_refresh(self, damage_options):
         if self.non_video_encodings:
             #refresh the whole window in one go:
             damage_options["novideo"] = True
-        WindowSource.full_quality_refresh(self, damage_options)
+        super().full_quality_refresh(damage_options)
 
 
     def quality_changed(self, window, *args):
-        WindowSource.quality_changed(self, window, args)
+        super().quality_changed(window, args)
         self.video_context_clean()
         return True
 
     def speed_changed(self, window, *args):
-        WindowSource.speed_changed(self, window, args)
+        super().speed_changed(window, args)
         self.video_context_clean()
         return True
 
@@ -587,18 +587,18 @@ def speed_changed(self, window, *args):
     def must_batch(self, delay):
         #force batching when using video region
         #because the video region code is in the send_delayed path
-        return self.video_subregion.rectangle is not None or WindowSource.must_batch(self, delay)
+        return self.video_subregion.rectangle is not None or super().must_batch(delay)
 
 
     def get_speed(self, encoding):
-        s = WindowSource.get_speed(self, encoding)
+        s = super().get_speed(encoding)
         #give a boost if we have a video region and this is not video:
         if self.video_subregion.rectangle and encoding not in self.video_encodings:
             s += 25
         return min(100, s)
 
     def get_quality(self, encoding):
-        q = WindowSource.get_quality(self, encoding)
+        q = super().get_quality(encoding)
         #give a boost if we have a video region and this is not video:
         if self.video_subregion.rectangle and encoding not in self.video_encodings:
             q += 40
@@ -608,7 +608,7 @@ def get_quality(self, encoding):
     def client_decode_error(self, error, message):
         #maybe the stream is now corrupted..
         self.cleanup_codecs()
-        WindowSource.client_decode_error(self, error, message)
+        super().client_decode_error(error, message)
 
 
     def get_refresh_exclude(self):
@@ -626,7 +626,7 @@ def refresh_subregion(self, regions):
         self.flush_video_encoder_now()
         encoding = self.auto_refresh_encodings[0]
         options = self.get_refresh_options()
-        WindowSource.do_send_delayed_regions(self, now, regions, encoding, options, get_best_encoding=self.get_refresh_subregion_encoding)
+        super().do_send_delayed_regions(now, regions, encoding, options, get_best_encoding=self.get_refresh_subregion_encoding)
         return True
 
     def get_refresh_subregion_encoding(self, *_args):
@@ -640,7 +640,7 @@ def get_refresh_subregion_encoding(self, *_args):
 
     def remove_refresh_region(self, region):
         #override so we can update the subregion timers / regions tracking:
-        WindowSource.remove_refresh_region(self, region)
+        super().remove_refresh_region(region)
         self.video_subregion.remove_refresh_region(region)
 
     def add_refresh_region(self, region):
@@ -651,7 +651,7 @@ def add_refresh_region(self, region):
         vr = self.video_subregion.rectangle
         if vr is None:
             #no video region, normal code path:
-            return WindowSource.add_refresh_region(self, region)
+            return super().add_refresh_region(region)
         if vr.contains_rect(region):
             #all of it is in the video region:
             self.video_subregion.add_video_refresh(region)
@@ -659,12 +659,12 @@ def add_refresh_region(self, region):
         ir = vr.intersection_rect(region)
         if ir is None:
             #region is outside video region, normal code path:
-            return WindowSource.add_refresh_region(self, region)
+            return super().add_refresh_region(region)
         #add intersection (rectangle in video region) to video refresh:
         self.video_subregion.add_video_refresh(ir)
         #add any rectangles not in the video region
         #(if any: keep track if we actually added anything)
-        return sum(WindowSource.add_refresh_region(self, r) for r in region.substract_rect(vr))
+        return sum(super().add_refresh_region(r) for r in region.substract_rect(vr))
 
     def matches_video_subregion(self, width, height):
         vr = self.video_subregion.rectangle
@@ -707,7 +707,7 @@ def send_nonvideo(regions=regions, encoding=coding, exclude_region=None, get_bes
             if self.b_frame_flush_timer and exclude_region is None:
                 #a b-frame is already due, don't clobber it!
                 exclude_region = vr
-            WindowSource.do_send_delayed_regions(self, damage_time, regions, encoding, options, exclude_region=exclude_region, get_best_encoding=get_best_encoding)
+            super().do_send_delayed_regions(damage_time, regions, encoding, options, exclude_region=exclude_region, get_best_encoding=get_best_encoding)
 
         if self.is_tray:
             sublog("BUG? video for tray - don't use video region!")
@@ -727,7 +727,7 @@ def send_nonvideo(regions=regions, encoding=coding, exclude_region=None, get_bes
 
         if not vr:
             sublog("no video region, we may use the video encoder for something else")
-            WindowSource.do_send_delayed_regions(self, damage_time, regions, coding, options)
+            super().do_send_delayed_regions(damage_time, regions, coding, options)
             return
         assert not self.full_frames_only
 
@@ -1023,7 +1023,7 @@ def update_encoding_options(self, force_reload=False):
 
             Can be called from any thread.
         """
-        WindowSource.update_encoding_options(self, force_reload)
+        super().update_encoding_options(force_reload)
         vs = self.video_subregion
         if vs:
             if (self.encoding!="auto" and self.encoding not in self.common_video_encodings) or \
@@ -1064,8 +1064,8 @@ def update_encoding_options(self, force_reload=False):
                             #we don't bother substracting new and old (too complicated)
                             refreshlog("scheduling refresh of old region: %s", old)
                             #this may also schedule a refresh:
-                            WindowSource.add_refresh_region(self, old)
-                        WindowSource.remove_refresh_region(self, newrect)
+                            super().add_refresh_region(old)
+                        super().remove_refresh_region(newrect)
                         if not self.refresh_regions:
                             self.cancel_refresh_timer()
                         if subregion_needs_refresh:
@@ -1720,13 +1720,13 @@ def get_fail_cb(self, packet):
         coding = packet[6]
         if coding in self.common_video_encodings:
             return None
-        return WindowSource.get_fail_cb(self, packet)
+        return super().get_fail_cb(packet)
 
 
     def make_draw_packet(self, x, y, w, h, coding, data, outstride, client_options, options):
         #overriden so we can invalidate the scroll data:
         #log.error("make_draw_packet%s", (x, y, w, h, coding, "..", outstride, client_options)
-        packet = WindowSource.make_draw_packet(self, x, y, w, h, coding, data, outstride, client_options, options)
+        packet = super().make_draw_packet(x, y, w, h, coding, data, outstride, client_options, options)
         sd = self.scroll_data
         if sd and not options.get("scroll"):
             if client_options.get("scaled_size") or client_options.get("quality", 100)<20:
@@ -1944,7 +1944,7 @@ def do_schedule_auto_refresh(self, encoding, data, region, client_options, optio
             #if there are non-scroll packets following this one, they will
             #and if not then we're OK anyway
             return
-        WindowSource.do_schedule_auto_refresh(self, encoding, data, region, client_options, options)
+        super().do_schedule_auto_refresh(encoding, data, region, client_options, options)
 
 
     def get_fallback_encoding(self, encodings, order):
diff --git a/src/xpra/sound/sink.py b/src/xpra/sound/sink.py
index bc8b783256..fd3b81f535 100755
--- a/src/xpra/sound/sink.py
+++ b/src/xpra/sound/sink.py
@@ -77,7 +77,7 @@ def __init__(self, sink_type=None, sink_options=None, codecs=(), codec_options=N
                 csv(codecs), csv(get_decoders().keys())))
         codec = matching[0]
         decoder, parser, stream_compressor = get_decoder_elements(codec)
-        SoundPipeline.__init__(self, codec)
+        super().__init__(codec)
         self.container_format = (parser or "").replace("demux", "").replace("depay", "")
         self.sink_type = sink_type
         self.stream_compressor = stream_compressor
diff --git a/src/xpra/sound/src.py b/src/xpra/sound/src.py
index 4d1278c920..e65fe61094 100755
--- a/src/xpra/sound/src.py
+++ b/src/xpra/sound/src.py
@@ -81,7 +81,7 @@ def __init__(self, src_type=None, src_options=None, codecs=(), codec_options=Non
             raise InitExit(1, "no matching codecs between arguments '%s' and supported list '%s'" % (csv(codecs), csv(get_encoders().keys())))
         codec = matching[0]
         encoder, fmt, stream_compressor = get_encoder_elements(codec)
-        SoundPipeline.__init__(self, codec)
+        super().__init__(codec)
         self.queue = None
         self.caps = None
         self.volume = None
diff --git a/src/xpra/sound/wrapper.py b/src/xpra/sound/wrapper.py
index bd425d2018..ae749528d3 100644
--- a/src/xpra/sound/wrapper.py
+++ b/src/xpra/sound/wrapper.py
@@ -87,7 +87,7 @@ def __init__(self, wrapped_object, method_whitelist, exports_list):
         #add bits common to both record and play:
         methods = method_whitelist+["set_volume", "cleanup"]
         exports = ["state-changed", "info", "error"] + exports_list
-        subprocess_callee.__init__(self, wrapped_object=wrapped_object, method_whitelist=methods)
+        super().__init__(wrapped_object=wrapped_object, method_whitelist=methods)
         for x in exports:
             self.connect_export(x)
 
@@ -103,7 +103,7 @@ def process_exit():
             def force_exit():
                 sys.exit(1)
             self.timeout_add(FAKE_CRASH*1000, force_exit)
-        subprocess_callee.start(self)
+        super().start(self)
 
     def cleanup(self):
         wo = self.wrapped_object
@@ -126,7 +126,7 @@ class sound_record(sound_subprocess):
     def __init__(self, *pipeline_args):
         from xpra.sound.src import SoundSource
         sound_pipeline = SoundSource(*pipeline_args)
-        sound_subprocess.__init__(self, sound_pipeline, [], ["new-stream", "new-buffer"])
+        super().__init__(sound_pipeline, [], ["new-stream", "new-buffer"])
         self.large_packets = [b"new-buffer"]
 
 class sound_play(sound_subprocess):
@@ -134,7 +134,7 @@ class sound_play(sound_subprocess):
     def __init__(self, *pipeline_args):
         from xpra.sound.sink import SoundSink
         sound_pipeline = SoundSink(*pipeline_args)
-        sound_subprocess.__init__(self, sound_pipeline, ["add_data"], [])
+        super().__init__(sound_pipeline, ["add_data"], [])
 
 
 def run_sound(mode, error_cb, options, args):
@@ -236,7 +236,7 @@ class sound_subprocess_wrapper(subprocess_caller):
         * forward get/set volume calls (get_volume uses the value found in "info")
     """
     def __init__(self, description):
-        subprocess_caller.__init__(self, description)
+        super().__init__(description)
         self.state = "stopped"
         self.codec = "unknown"
         self.codec_description = ""
@@ -315,7 +315,7 @@ def get_volume(self):
 class source_subprocess_wrapper(sound_subprocess_wrapper):
 
     def __init__(self, plugin, options, codecs, volume, element_options):
-        sound_subprocess_wrapper.__init__(self, "sound source")
+        super().__init__("sound source")
         self.large_packets = [b"new-buffer"]
         self.command = get_full_sound_command()+[
             "_sound_record", "-", "-",
@@ -338,7 +338,7 @@ def __repr__(self):
 class sink_subprocess_wrapper(sound_subprocess_wrapper):
 
     def __init__(self, plugin, codec, volume, element_options):
-        sound_subprocess_wrapper.__init__(self, "sound output")
+        super().__init__("sound output")
         self.large_packets = [b"add_data"]
         self.codec = codec
         self.command = get_full_sound_command()+[
diff --git a/src/xpra/x11/gtk_x11/clipboard.py b/src/xpra/x11/gtk_x11/clipboard.py
index 86fd54f27d..604ca9ba71 100644
--- a/src/xpra/x11/gtk_x11/clipboard.py
+++ b/src/xpra/x11/gtk_x11/clipboard.py
@@ -76,7 +76,7 @@ def __init__(self, send_packet_cb, progress_cb=None, **kwargs):
         self.init_window()
         init_x11_filter()
         self.x11_filter = True
-        ClipboardTimeoutHelper.__init__(self, send_packet_cb, progress_cb, **kwargs)
+        super().__init__(send_packet_cb, progress_cb, **kwargs)
 
     def __repr__(self):
         return "X11Clipboard"
@@ -174,12 +174,12 @@ def do_xpra_property_notify_event(self, event):
     def _munge_raw_selection_to_wire(self, target, dtype, dformat, data):
         if dformat==32 and dtype in ("ATOM", "ATOM_PAIR"):
             return "atoms", _filter_targets(xatoms_to_strings(data))
-        return ClipboardProtocolHelperCore._munge_raw_selection_to_wire(self, target, dtype, dformat, data)
+        return super()._munge_raw_selection_to_wire(target, dtype, dformat, data)
 
     def _munge_wire_selection_to_raw(self, encoding, dtype, dformat, data):
         if encoding=="atoms":
             return strings_to_xatoms(_filter_targets(data))
-        return ClipboardProtocolHelperCore._munge_wire_selection_to_raw(self, encoding, dtype, dformat, data)
+        return super()._munge_wire_selection_to_raw(encoding, dtype, dformat, data)
 
 GObject.type_register(X11Clipboard)
 
diff --git a/src/xpra/x11/models/base.py b/src/xpra/x11/models/base.py
index 7194107e90..f5729a4514 100644
--- a/src/xpra/x11/models/base.py
+++ b/src/xpra/x11/models/base.py
@@ -646,4 +646,4 @@ def update_wm_state(prop):
         # it may make sense to apply it to the client_window
         # whereas the code in WindowModel assumes there is a corral window
         #not handled:
-        return CoreX11WindowModel.process_client_message_event(self, event)
+        return super().process_client_message_event(event)
diff --git a/src/xpra/x11/models/window.py b/src/xpra/x11/models/window.py
index fc4699758e..d8ea9e9192 100644
--- a/src/xpra/x11/models/window.py
+++ b/src/xpra/x11/models/window.py
@@ -335,7 +335,7 @@ def do_unmanaged(self, wm_exiting):
                 self.client_window.show_unraised()
             #it is now safe to destroy the corral window:
             cwin.destroy()
-        BaseWindowModel.do_unmanaged(self, wm_exiting)
+        super().do_unmanaged(wm_exiting)
 
 
     #########################################
@@ -366,7 +366,7 @@ def map(self):
     def do_xpra_property_notify_event(self, event):
         if event.delivered_to is self.corral_window:
             return
-        BaseWindowModel.do_xpra_property_notify_event(self, event)
+        super().do_xpra_property_notify_event(event)
 
     def do_child_map_request_event(self, event):
         # If we get a MapRequest then it might mean that someone tried to map
@@ -621,7 +621,7 @@ def process_client_message_event(self, event):
             with xswallow:
                 X11Window.configureAndNotify(self.xid, x, y, w, h)
             return True
-        return BaseWindowModel.process_client_message_event(self, event)
+        return super().process_client_message_event(event)
 
     def calc_constrained_size(self, w, h, hints):
         mhints = typedict(hints)
diff --git a/src/xpra/x11/server.py b/src/xpra/x11/server.py
index 91487734b3..70a62f9337 100644
--- a/src/xpra/x11/server.py
+++ b/src/xpra/x11/server.py
@@ -320,12 +320,12 @@ def get_server_mode(self):
 
 
     def server_event(self, *args):
-        X11ServerBase.server_event(self, *args)
+        super().server_event(*args)
         self.emit("server-event", args)
 
 
     def make_hello(self, source):
-        capabilities = X11ServerBase.make_hello(self, source)
+        capabilities = super().make_hello(source)
         if source.wants_features:
             capabilities["pointer.grabs"] = True
             updict(capabilities, "window", {
@@ -347,7 +347,7 @@ def make_hello(self, source):
     # info:
     #
     def do_get_info(self, proto, server_sources):
-        info = X11ServerBase.do_get_info(self, proto, server_sources)
+        info = super().do_get_info(proto, server_sources)
         info.setdefault("state", {}).update({
                                              "focused"  : self._has_focus,
                                              "grabbed"  : self._has_grab,
@@ -355,7 +355,7 @@ def do_get_info(self, proto, server_sources):
         return info
 
     def get_ui_info(self, proto, wids=None, *args):
-        info = X11ServerBase.get_ui_info(self, proto, wids, *args)
+        info = super().get_ui_info(proto, wids, *args)
         #_NET_WM_NAME:
         wm = self._wm
         if wm:
@@ -363,7 +363,7 @@ def get_ui_info(self, proto, wids=None, *args):
         return info
 
     def get_window_info(self, window):
-        info = X11ServerBase.get_window_info(self, window)
+        info = super().get_window_info(window)
         info.update({
                      "focused"  : self._has_focus and self._window_to_id.get(window, -1)==self._has_focus,
                      "grabbed"  : self._has_grab and self._window_to_id.get(window, -1)==self._has_grab,
@@ -1057,7 +1057,7 @@ def _set_client_properties(self, proto, wid, window, new_client_properties):
             #we have handled it on the window directly, so remove it from client properties
             del new_client_properties["workspace"]
         #handle the rest as normal:
-        X11ServerBase._set_client_properties(self, proto, wid, window, new_client_properties)
+        super()._set_client_properties(proto, wid, window, new_client_properties)
 
 
     """ override so we can raise the window under the cursor
@@ -1072,7 +1072,7 @@ def _move_pointer(self, wid, pos, *args):
                 mouselog("raising %s", window)
                 with xswallow:
                     window.raise_window()
-        X11ServerBase._move_pointer(self, wid, pos, *args)
+        super()._move_pointer(wid, pos, *args)
 
 
     def _process_close_window(self, proto, packet):
diff --git a/src/xpra/x11/server_keyboard_config.py b/src/xpra/x11/server_keyboard_config.py
index a5e150a4d7..829a5b74ea 100644
--- a/src/xpra/x11/server_keyboard_config.py
+++ b/src/xpra/x11/server_keyboard_config.py
@@ -133,7 +133,7 @@ def get_info(self) -> dict:
     def parse_options(self, props):
         """ used by both process_hello and process_keymap
             to set the keyboard attributes """
-        KeyboardConfigBase.parse_options(self, props)
+        super().parse_options(props)
         modded = {}
         def parse_option(name, parse_fn, *parse_args):
             prop = "xkbmap_%s" % name
diff --git a/src/xpra/x11/uinput_device.py b/src/xpra/x11/uinput_device.py
index a0f3a6559f..b83b0d38e8 100644
--- a/src/xpra/x11/uinput_device.py
+++ b/src/xpra/x11/uinput_device.py
@@ -144,7 +144,7 @@ def move_pointer(self, screen_no, x, y, *_args):
 class UInputTouchpadDevice(UInputDevice):
 
     def __init__(self, device, device_path, root_w, root_h):
-        UInputDevice.__init__(self, device, device_path)
+        super().__init__(device, device_path)
         self.root_w = root_w
         self.root_h = root_h
 
diff --git a/src/xpra/x11/x11_server_base.py b/src/xpra/x11/x11_server_base.py
index 4aee77c909..ebceda0476 100644
--- a/src/xpra/x11/x11_server_base.py
+++ b/src/xpra/x11/x11_server_base.py
@@ -63,7 +63,7 @@ def __init__(self, clobber):
         self.display_pid = 0
 
     def do_init(self, opts):
-        X11ServerCore.do_init(self, opts)
+        super().do_init(opts)
         self._xsettings_enabled = opts.xsettings
         if self._xsettings_enabled:
             from xpra.x11.xsettings import XSettingsHelper
diff --git a/src/xpra/x11/x11_server_core.py b/src/xpra/x11/x11_server_core.py
index e8f0530752..15d8507f80 100644
--- a/src/xpra/x11/x11_server_core.py
+++ b/src/xpra/x11/x11_server_core.py
@@ -347,7 +347,7 @@ def set_keyboard_repeat(self, key_repeat):
             keylog("keyboard repeat disabled")
 
     def make_hello(self, source):
-        capabilities = GTKServerBase.make_hello(self, source)
+        capabilities = super().make_hello(source)
         capabilities["server_type"] = "Python/gtk/x11"
         if source.wants_features:
             capabilities.update({
@@ -368,7 +368,7 @@ def make_hello(self, source):
 
     def do_get_info(self, proto, server_sources):
         start = monotonic_time()
-        info = GTKServerBase.do_get_info(self, proto, server_sources)
+        info = super().do_get_info(proto, server_sources)
         if self.opengl_props:
             info["opengl"] = self.opengl_props
         sinfo = info.setdefault("server", {})
@@ -382,7 +382,7 @@ def do_get_info(self, proto, server_sources):
 
     def get_ui_info(self, proto, wids=None, *args):
         log("do_get_info thread=%s", threading.current_thread())
-        info = GTKServerBase.get_ui_info(self, proto, wids, *args)
+        info = super().get_ui_info(proto, wids, *args)
         #this is added here because the server keyboard config doesn't know about "keys_pressed"..
         if not self.readonly:
             with xlog: