Automatic highlight while editing enums, structs, and functions makes text unreadable

Hi George,

From your screenshot, that box isn't a normal selection/reference highlight. It's the rename suggestion: when you change the name of a symbol at its declaration (enum member, struct, function), Visual Studio marks the edited identifier with a dashed box and shows the light bulb offering "Rename '<old>' to '<new>'" for the other references. The problem is that the background color used for that marker has very poor contrast in the Dark theme.

You can change that color:

1. Go to Tools > Options > Environment > Fonts and Colors.
2. Make sure "Show settings for:" is set to "Text Editor".
3. In "Display items", look for the refactoring/rename suggestion entry (in earlier versions it was named "Refactoring Suggestion"; type "Refactoring" or "Rename" with the list focused to jump to it).
4. Change its "Item background" to a darker color (or set it to Default/Automatic) and click OK. Reopen the file if the change doesn't apply right away.

Notes:

• "Disable Reference Highlighting" under the C/C++ options controls a different feature (highlighting all occurrences of the selected symbol), so it won't affect this box.
• The marker disappears once you accept the rename from the light bulb (or Ctrl+.) or move on, so it's only shown while the edit is "pending".
• If the colors still look wrong after changing them, try Tools > Import and Export Settings > Reset all settings (export a backup first), since a stale Fonts and Colors cache can keep old colors.

If you can tell us your Visual Studio version (Help > About), I can point you to the exact item name for that version.

Sources:

• Sysprogs forum – Highlight issues in Visual Studio’s Dark Theme
• Microsoft Learn – Options, Text Editor, C/C++, Advanced