Blanking `editor.minimap.markSectionHeaderRegex` causes high CPU usage in `Code Helper (Renderer)` process on MacOS

[swlody]

Does this issue occur when all extensions are disabled?: Yes

• VS Code Version: 1.101.0
• OS Version: Darwin arm64 24.5.0

Steps to Reproduce:

1. Set editor.minimap.markSectionHeaderRegex to empty string
2. Observe high CPU usage in Code Helper (Renderer) process

I deleted the regex because it was falsely matching some code in an HTML template file (I didn't know about editor.minimap.showRegionSectionHeaders) and causing the minimap to render strangely. On Mac OS this causes a single CPU core to spin at 100% indefinitely. Resetting the setting to the default value and restarting the VSCode process returns CPU usage to normal.