We should try to get rid of this liability asap. Let's track upstream's progress here.
upstream has merged qt6 support: https://github.com/nextcloud/desktop/pull/4584
Nice! All of these were pushed just after the recent release, hopefully this means we can close this bug after the next. This will need a bit of ebuild work - qt5/qt6 + switching webengine to qt6 only Also the deps for dolphin, seeing the mask message for recently added plasma 6