SUMMARY If adaptive sync is enabled on the monitor, when attempting to screenshot with rectangular region, display turns black and only comes back when the screenshot is cancelled. My monitor is Sceptre E248B-FPT168 (1080p 165Hz) STEPS TO REPRODUCE 1. enable adaptive sync 2. take a screenshot with rectangular region 3. display turns black OBSERVED RESULT Display turns black EXPECTED RESULT Display should not turn black when adaptive sync is enabled SOFTWARE/OS VERSIONS Linux/KDE Plasma: Kubuntu 24.10 KDE Plasma Version: 6.1.5 KDE Frameworks Version: 6.6.0 Qt Version: 6.6.2 Kernel Version: 6.11.0-13-generic (64-bit) Graphics Platform: Wayland ADDITIONAL INFORMATION
I can confirm that I'm experiencing this bug. I have a dual-monitor setup with an ASUS VG27A (1440p 165hz) display and an FMC 1080p60 display, where the former has adaptive sync and the latter does not. When adaptive sync is "automatic" on the ASUS display, taking a screenshot as specified in the report will black out the ASUS display, while allowing a region to be selected as usual on the FMC display. I might also note that when adaptive sync is set to "Always" on the ASUS display, it ceases to work entirely until the settings auto-revert - this may be a related issue.
Attempted this on another monitor (Koorui GP-01, 1440p, 165 Hz, adaptive sync enabled), but Spectacle seems to work fine here. Not quite sure what the pattern is between the monitors that have this bug vs. those that don't, but it does appear to be dependent on the monitor used. (In both cases the monitor is connected via DisplayPort)
Please report this to your driver vendor (at https://gitlab.freedesktop.org/drm/amd/-/issues for AMD, https://forums.developer.nvidia.com/c/gpu-graphics/linux for NVidia); KWin only turns on VRR and it's up to the driver to make it work. Most likely the signal is getting out of the valid refresh rate range, and not all displays handle that nicely, but it might be something else as well.
Filed bug report here: https://gitlab.freedesktop.org/drm/amd/-/issues/3924