Back out fallback icon support which does not work as intended The fallback icon support does not work as intended since it depends on gtk_icon_theme_has_icon() in order to determine whether an icon exists in the current icon theme. Contrary to the documentation GtkIconTheme not only falls back to the "hicolor" theme but also to the "Adwaita" and "gnome" themes when looking for icons. The Adwaita theme provides the "system-software-update", "software-update-available", and "software-update-urgent" icons so the fallback will never be used even if the current theme does not provide these icons. SNI host implementations such as the one in KDE Plasma Shell will only look for icon names in the current theme and do not fall back to the "Adwaita" and "gnome" themes.

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513f5478a711c8fa9a7609d6234ea0dced956bd0 version-2
4196eacbe940b5a3661f6de083c8dcae6ce60d66 version-3
74644b419e868742147e07169e9e1035a9ece91e version-4
8c5aee997afa0cb4a0b1f998c5a50024a48f1ac6 version-5