Scintilla seems to have catched a bug during development. I can not remeber the IDE ever misplacing any chars of the source code, however since i updated my system (Windows) some months ago it seems to have trouble with. See the image please (terribly enlarged, i don't know why).
This appears some time with re-loaded code (after restarting the ide). I can not further describe the origin of this. Seems messy and stops development...
Tested and found in 5.51 x86 and 5.72 x86 using system DPI scaling (200%)
IDE uses system dpi scaling override "system (extended)" to enlarge toolbar icons (they're otherwise at 50% size).