If GTK decides to print a lot of warnings to stderr when started as part of the graphical sudo relaunch prompt and the user either fails to authenticate or decides to press "Cancel", these GTK warnings will be shown in the succeeding error dialog. This is somewhat acceptable if there are only a couple of warnings printed by GTK. However, this becomes more problematic on systems where GTK decides to print a large number of warnings. For example, if the user has an old GTK theme enabled that makes use of many deprecated features. In this case, it is possible that the warning output from GTK will span a significant number of lines and thus result in an error dialog that is far higher than the screen. This will result in the dialog buttons ending up outside the screen. This is especially problematic since a first-time user does not know that the only available button is "Cancel" and that they can just close the window. Additionally, the relevant error message is also likely to be obstructed since it generally ends up at the end of the message. Steps to reproduce: 1. On Fedora 35, set the GTK theme to "Xfce" (shipped as part of the XFCE DE) 2. Run ./install-server (observed on both 4.14.0 and the latest development build) 3. Proceed to the sudo relaunch prompt 4. Press cancel 5. You now get an error dialog that is higher than 1200 pixels
Below are some examples of the kind of GTK warnings we get in the above scenario: > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:451:35: The style property GtkWidget:focus-line-pattern is deprecated and shouldn't be used anymore. It will be removed in a future version > > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:460:19: The :insensitive pseudo-class is deprecated. Use :disabled instead. > > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:483:22: Custom CSS properties are no longer supported. > > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:496:30: The :insensitive pseudo-class is deprecated. Use :disabled instead. > > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:496:62: The :insensitive pseudo-class is deprecated. Use :disabled instead. > > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:521:28: The :insensitive pseudo-class is deprecated. Use :disabled instead. > > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:521:58: The :insensitive pseudo-class is deprecated. Use :disabled instead. > > (tl-ssh-askpass.py:2140345): Gtk-WARNING **: 13:30:46.599: Theme parsing error: gtk.css:537:22: Custom CSS properties are no longer supported.
