Bug 505017

Created attachment 181897 [details]
A video showing the issue and detailed system information

SUMMARY
Since a few days, Krita doesn't allow to freely draw on the canvas. When trying to draw, a part of the canvas in the center of the window shows the system cursor, rather than the draw cursor, and trying to draw yields no results. A few parts of the canvas show the draw cursor and allow to draw. In fact, it is possible to draw into the affected area from the outside, just not to start inside the area.

At the edges of the affected area the cursor is the window resize cursor, which implies some invisible window taking the focus from the canvas. In fact, moving the canvas or main window does make the affected area drawable.

STEPS TO REPRODUCE
1. Launch Krita
2. Create a new file with A4 600 DPI setting
3. Try to draw on several parts of the canvas with a mouse or tablet
4. Move the window or canvas from the center
5. Try to draw again

OBSERVED RESULT
When moving the cursor, the center part of the canvas shows the system cursor, rather than the draw cursor, preventing to draw on the canvas. Moving the canvas or window from the center allows to draw again.

EXPECTED RESULT
The whole canvas should allow to draw without the need to move canvas or window.

SOFTWARE/OS VERSIONS
Linux, Flatpak distribution from Flathub.
Core System: Fedora 42 Silverblue with GNOME Desktop
Qt Version: 5.15.7

ADDITIONAL INFORMATION
Attachments contains a video showing the issue, as well as detailed system information.