Open Kate, move mouse cursor in text area. After short pause the cursor hides (as intended), i.e. DrmOutput::hideCursor() is called. Bug: A quick black flash appears from bottom till cursor position. My guess is, that calling drmModeSetCursor(m_backend->fd(), m_crtc->id(), 0, 0, 0) in between presents is the cause. We could: * Try to synchronize it with present (difficult in legacy mode, possible in AMS after we introduced a cursor plane instead of using drmModeSetCursor). * For hideCursor() instead of removing the cursor via drmModeSetCursor(..) show a transparent cursor image.
rendering a transparent cursor instead seams fine to me as a workaround. Personally I have never seen this happening. Maybe driver bug?
Cannot reproduce this bug both in Wayland and X11 Intel+NVIDIA video cards Operating System: KDE neon Developer Edition KDE Plasma Version: 5.14.80 Qt Version: 5.11.1 KDE Frameworks Version: 5.51.0 Kernel Version: 4.15.0-34-generic
Can reproduce black flash in Wayland on 5.17.80 Operating System: Arch Linux KDE Plasma Version: 5.17.80 KDE Frameworks Version: 5.64.0 Qt Version: 5.13.1 Kernel Version: 5.3.6-arch1-1-fsync OS Type: 64-bit Processors: 12 × AMD Ryzen 5 2600 Six-Core Processor Memory: 15.7 GiB of RAM GPU: Sapphire RX 560 8GB Mesa 19.3.0-devel (git-fe930ad92a) (Valve ACO)
i saw this bug on Fedora 33 Rawhide with Plasma 5.18.2 in wayland while was writing a script in kwrite. I tried to reproduce but i dont have any sucess. Qt Version: 5.13.2 Kernel: 5.6 Release Candidate 3 (Fedora Rawhide default in 29/02/2020) GPU: AMD Radeon Sapphire OC RX550 2GB Polaris12/Lexa Pro Mesa: 20.0.0(Default too)
5.18 is really old by now and I haven't seen this happen myself, so I assume this is no longer a problem. If it is still reproducible in 5.27, just reopen the bug report