Sublime Text 4 rendering issues on macOS 11.2

[tomcat]

How can I fix this?

[OdatNurd]

The theme you’re using is missing one or more textures; that colorful little patch is the placeholder.

If you’re using Default or Adaptive, check to see if you have an override or customization on those (Preferences > Browse Packages; do you see Theme - Default there; if yes, move it away) or if you have a sublime-theme file in your User package with the same name (if you do, also move it away).

If you’re not using either of those themes, then the theme you’re using needs to be updated to support ST4; contact the author of the theme.