The gtk3-nocsd (double-headerbar) issue had reappeared after updates in Ubuntu Unity 22.04, and has been fixed in the 22.04.1 ISO. This is also the first release of Ubuntu Unity which uses Unity 7.6. Ubuntu Unity 22.04.1 doesn’t use the Yaru-Unity theme, as support for Unity7 has been upstreamed to Yaru. The Appearance settings in Unity Control Center have been fixed. You can now set a desktop accent color from Unity Control Center too.
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