Work around bug in Selenium 3.4.3 + Chrome 60

gratipay/testing/browser.py

@@ -7,6 +7,9 @@
 import time
 
 from splinter.browser import _DRIVERS
+from splinter.driver.webdriver import WebDriverElement
+from selenium.common.exceptions import WebDriverException
+from selenium.webdriver.common.keys import Keys
 
 from gratipay.security import user
 
@@ -22,6 +25,17 @@ class NeverLeft(Exception): pass
 class NeverShowedUp(Exception): pass
 
 
+# Monkey-patch .click to work around stackoverflow.com/q/11908249
+def monkey_click(self):
+    try:
+        self._element.click()                   # Firefox 55
+    except WebDriverException as exc:
+        if not exc.msg.startswith('unknown error: Element is not clickable'):
+            raise
+        self._element.send_keys(Keys.RETURN)    # Chrome 60
+WebDriverElement.click = monkey_click
+
+
 class BrowserHarness(Harness):
     """This is a harness for through-the-web (TTW) testing. It passes
     everything through to an underlying `Splinter`_ browser, with the following