GNOME shell crashes when dash-to-dock extension is disabled in overview

[taoky]

With current code from master (1053b3e), dash-to-dock would make shell crash in both GNOME 45 and 46. This could be reproduced by:

1. Open Overview (both window picker and app grid could trigger this)
2. Lock the screen, or run gnome-extensions disable [email protected] if sshing.

My local bisecting result shows that de35ab6 is the first bad commit (weird) when testing with GNOME 45. And this diff patch "workarounds" the crash in both GNOME 45 and 46:

diff --git a/_stylesheet.scss b/_stylesheet.scss
index b23cc43..adc45af 100644
--- a/_stylesheet.scss
+++ b/_stylesheet.scss
@@ -251,10 +251,6 @@ $dock_style_modes: [null, shrink, extended, extended-shrink];
     }
 }
 
-.dash-item-container .overview-tile .overview-icon,
-.dash-item-container .show-apps .overview-icon {
-    background-color: rgba(255,255,255,0);
-}
 
 .dash-item-container .overview-tile:hover .overview-icon,
 .dash-item-container .overview-tile.focused .overview-icon,

This issue looks like https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/7339 but it's slightly different (crashing widget is Gjs_ui_dash_ShowAppsIcon), and I have tried to find the cause but no clue. And this bug, if exists in shell, could only be triggered by an extension. I have also tried to build a simpler extension example, but it does not crash with a CSS-only extension.

bt full (GNOME 46):
bt-full-fedora-gnome46.txt

[vanvugt]

Thanks for the bug report. dash-to-dock shouldn't be able to cause a segfault like that, and particularly not with style changes. It looks like we should track this upstream just keeping in mind the only way to reproduce it is with dash-to-dock.

[vanvugt]

I'm working on an upstream fix so let's track this in https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/7339 instead.