I Experienced this problem and "sudo apt remove libqt5quick5-gles" followed by a reboot corrected the problem completely. Attached are the requested logs.
** Attachment added: "Requested upgrade logs" https://bugs.launchpad.net/ubuntu/+source/qtdeclarative-opensource-src/+bug/1920130/+attachment/5483583/+files/upgrade-logs.tgz -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1920130 Title: System icons missing in kubuntu 21.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qtdeclarative-opensource-src/+bug/1920130/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs