bpo-41754: Ignore NotADirectoryError in invocation of xdg-settings (GH-23075)

It is not clear why this can happen, but several users have mentioned
getting this exception on macOS.
(cherry picked from commit 23831a7)

Co-authored-by: Ronald Oussoren <[email protected]>

Author: miss-islington

Lib/webbrowser.py

@@ -550,7 +550,7 @@ def register_standard_browsers():
                 cmd = "xdg-settings get default-web-browser".split()
                 raw_result = subprocess.check_output(cmd, stderr=subprocess.DEVNULL)
                 result = raw_result.decode().strip()
-            except (FileNotFoundError, subprocess.CalledProcessError, PermissionError) :
+            except (FileNotFoundError, subprocess.CalledProcessError, PermissionError, NotADirectoryError) :
                 pass
             else:
                 global _os_preferred_browser

Misc/NEWS.d/next/Library/2020-11-01-15-07-20.bpo-41754.DraSZh.rst

@@ -0,0 +1 @@
+webbrowser: Ignore *NotADirectoryError* when calling ``xdg-settings``.