Problem capturing KDE Plasma window decorations

[SeongGino]

slop seems to have problems capturing selected windows in KDE Plasma 5(.27).

GTK 3/4 apps can capture the whole window just fine. But screenshots of QT apps or anything that Plasma decorates, sort of... does, and doesn't capture properly.

By default, it seems to capture the area of the Plasma-generated window bar, but is instead rendering the backdrop/some leftover compositor data? (Also doesn't seem to capture the thin window border)

Resizing a window manually demonstrates a different effect, but is still not quite right.

And the problem is exacerbated when a window resizes itself.

Not sure if this affects other desktop environments but wanted to make note of it regardless. Also affects maim when running with maim -s.