Created attachment 142395 [details] video of normal vs incorrect behavior SUMMARY When using certain programs such as Kate or Konsole, and the global scale is set to 175% or 200%, the mouse will grab the window instead of the scrollbar when the mouse position is at the very right edge of the screen and the application is maximized. STEPS TO REPRODUCE 1. Display Configuration -> set Global scale to 175% or 200% 2. Log out and in again to apply the scaling. 3. Open Konsole 4. Type a commmand to produce a large list of files such as `find` 5. Maximize the Konsole window. 6. If you have multiple monitors, make sure Konsole is on the right most monitor. 7. Move your mouse to the right edge of the screen, hold left click, then move the mouse up or down. OBSERVED RESULT The window is grabbed and starts moving around as if you grabbed the title bar to move the window. EXPECTED RESULT The scrollbar is grabbed and you can scroll the window, like you can when the scaling is normal. SOFTWARE/OS VERSIONS Windows: macOS: Linux/KDE Plasma: Arch Linux (available in About System) KDE Plasma Version: 5.22.5 KDE Frameworks Version: 5.87.0 Qt Version: 5.15.2 ADDITIONAL INFORMATION It used to work correctly about a year ago. I'm not sure exactly when or what component version broke it. Attached is a video of the bug. At first it shows how it should work. The 2nd clip shows the incorrect window grabbing behavior.
I tested it with wayland and turns out this only happens on X11.
It looks like there's a gap between the scrollbar and the right edge of the window. Can you try changing "windows' drag mode" in breeze settings? Go to Appearance > Application Style and click the button with a pencil icon in the bottom right corner of the "Breeze" item.
That setting prevents the window from moving, however the scrollbar still isn't getting grabbed.
Can confirm. Reminds me of Bug 428895. These are these 1px gaps all over the place on X11, sadly. I recommend using Wayland for a superior high DPI experience, if you're able to.
I can confirm this problem also with 175% scaling on Kubuntu 23.10 (KDE Plasma: 5.27.8). ... Took me hours to identify the culprit. :-/
If you're using fractional scaling in a Wayland session, that's a separate bug: Bug 459373 if the window is using XWayland, and Bug 480171if it's a native Wayland window.
Adding the x11-only keyword