I have been using qt5ct and qt6ct to enforce dark themes for Qt applications under COSMIC. After a recent update (within the last couple of weeks), this no longer behaves as expected. Some Qt applications now follow COSMIC’s native theming correctly, but others are being forced into light mode and no longer respect the environment variables defined by qt5ct or qt6ct. In my case, KRename is consistently affected.
This does not appear to be strictly a Qt5 vs Qt6 problem. For example, Fedora Media Writer (which I believe is Qt5, though I may be mistaken) follows dark mode correctly, and my Qt6 applications appear to behave properly as well. KRename I believe is also Qt5-based, but regardless of the framework version, the behavior is inconsistent across Qt applications.
I do not necessarily require user-defined environment variables to take precedence over COSMIC’s configuration. However, if COSMIC is now explicitly managing QT_QPA_PLATFORMTHEME or related Qt environment variables, then applications that do not properly follow the system dark/light preference should be addressed. The core issue is consistency: I want all applications to respect the selected dark mode where supported, and that is currently not happening. There may be room for discussion about whether COSMIC should allow user-defined variables to override its defaults, but from an end-user perspective the primary concern is achieving uniform dark mode behavior across Qt applications which in my case is no longer is possible where it was before.
I have been using qt5ct and qt6ct to enforce dark themes for Qt applications under COSMIC. After a recent update (within the last couple of weeks), this no longer behaves as expected. Some Qt applications now follow COSMIC’s native theming correctly, but others are being forced into light mode and no longer respect the environment variables defined by qt5ct or qt6ct. In my case, KRename is consistently affected.
This does not appear to be strictly a Qt5 vs Qt6 problem. For example, Fedora Media Writer (which I believe is Qt5, though I may be mistaken) follows dark mode correctly, and my Qt6 applications appear to behave properly as well. KRename I believe is also Qt5-based, but regardless of the framework version, the behavior is inconsistent across Qt applications.
I do not necessarily require user-defined environment variables to take precedence over COSMIC’s configuration. However, if COSMIC is now explicitly managing QT_QPA_PLATFORMTHEME or related Qt environment variables, then applications that do not properly follow the system dark/light preference should be addressed. The core issue is consistency: I want all applications to respect the selected dark mode where supported, and that is currently not happening. There may be room for discussion about whether COSMIC should allow user-defined variables to override its defaults, but from an end-user perspective the primary concern is achieving uniform dark mode behavior across Qt applications which in my case is no longer is possible where it was before.