Switching workspaces draws previous window's content on other windows' borders (possibly caused by scaling)

[KATANAND]

Hyprland version

Hyprland 0.50.1 built from branch v0.50.1-b at commit 4e242d0 ([gha] Nix: update inputs).
edit: (also see my last update comment)

Regression

been using this wm only for 2 month and think it was present all the time
edit: ~7 months already

Describe the bug

If i open one (fullscreen) window_1 on a workspace_X and then switch to workspace_Y, where i have window_2 and window_3 in split mode (with gaps around each possible side) so that their borders overlap with the area of window_1,
the pixels that are occupied by these 2 windows' borders inherit the color of the pixels that were rendered for window_1's content at that place.

Reproduction steps

1. On workspace1: open any 2 windows in (vertical) split mode
2. On workspace2: open browser(or whatever, e.g. swayimg) with with a yellow image and press F11 to get 100% fullscreen
3. Switch to workspace1 and see that borders around the 2 windows are yellow

Important notes

• This is the minimum config required to reproduce. systeminfo.txt contains full config that was used for reproducing, but 100% of what's left is bind = blah blah and is not related to the issue.

  monitor = , highres, auto, 1.33
  general {
      border_size = 0
  }
  animations:enabled = false

• With animations:enabled = true the artifacts are present horizontally (lines at top/bottom), but vertical gap doesn't get artifacts (this seems like when switching workspaces animations redraw this part of screen).
• This bug does not appear if i change config to use monitor = , highres, auto, 1 or monitor = , highres, auto, 2

Screenshot

open Wayland logo in browser -> F11 -> switch to another workspace

When i set monitor = , highres, auto, 1.33

When i set monitor = , highres, auto, 1.5 or comment out monitor = ...

System info and config

systeminfo.txt
(The hyprland.conf in systeminfo.txt is a result of me deleting everything (except keybinds) from my main config that does not cause the issue; so, basically, the aforementioned (in #Important-notes) repo config lines plus my personal keybindings)

[KATANAND]

My GPU (output of lspci, just as in systeminfo.txt):
NVIDIA Corporation TU117M [GeForce GTX 1650 Mobile / Max-Q] (rev a1)

I only use nouveau drivers. Proprietary drivers cause pain with my GPU on any distro. Last time i've tried propretary drivers i think i was still using X11. Also i use hybrid mode on my laptop, because if i enable "discrete gpu" mode in UEFI, i can't control brightness in any way.

Just in case, here is my full daily-driver config:
config.txt

There i use gaps_* = 0 (and default border_size = 1).

With such config, there is no space for the described artifacts and as a result there are none, but ...
i use waybar and even while there are no artifacts between windows' borders, the "line" between opened window(s) and waybar gets "colored".

[KATANAND]

Update since my initial report:
Hyprland: 0.50.1 -> 0.52.1
Kernel: 6.12.40 -> 6.18.2
NixOS 25.05 -> 25.11

The repro config still works (i.e. gives artifacts)

monitor = , highres, auto, 1.33
general {
    border_size = 0
}
animations:enabled = false

here is the updated output of hyprctl systeminfo -c > systeminfo.txt:
systeminfo.txt
It has my current config (that hasn't really changed since, and there isn't anything that triggers the bug beyond the ~3 config lines from above)