add example for overriding individiual DBus filter to firejail-profil…

…e.txt

See discussion in #3326.

src/man/firejail-profile.txt

@@ -496,6 +496,22 @@ Allow the application to talk to the name org.freedesktop.Notifications on the s
 .TP
 \fBnodbus \fR(deprecated)
 Disable D-Bus access (both system and session buses). Equivalent to dbus-system none and dbus-user none.
+.br
+
+.br
+Individual filters can be overridden via the \-\-ignore command. Supposing a profile has
+
+[...]
+dbus-user filter
+dbus-user.own org.mozilla.firefox.*
+dbus-user.talk org.freedesktop.Notifications
+dbus-system none
+[...]
+
+and the user wants to disable notifications, this can be achieved by putting the below in a local override file:
+[...]
+ignore dbus-user.talk org.freedesktop.Notifications
+[...]
 
 .SH Resource limits, CPU affinity, Control Groups
 These profile entries define the limits on system resources (rlimits) for the processes inside the sandbox.