Hey, this is a known issue with how the editor Monaco and VS Code measures character widths for monospaced fonts. Some font plus size combos cause subpixel rounding differences, so the cursor position shifts.
A couple of workarounds:
- Use JetBrains Mono Regular instead of JetBrains Mono SemiBold. Regular is more likely to be detected correctly.
- Use font size 13 or 15, like you already found.
- Try adding this to settings.json:
"editor.fontWeight": "600"instead of using SemiBold in the font name. Sometimes that helps.
Similar reports:
Sadly, the root cause is upstream in VS Code or Chromium font rendering, so it’s hard for us to fully fix on our side.