Why are my custom colors not updating in the block editor?

If you have modified your JSON file but the old colors still appear in the editor, this is almost always a caching issue. WordPress aggressively caches the results of the theme.json file. Furthermore, any changes saved previously in the database via the Site Editor interface will override your file changes. Clear your browser cache and select "Clear customizations" in the Site Editor Styles panel to fix this.

Why am I getting a White Screen of Death (WSOD) in Gutenberg?

A white screen or a broken block editor layout immediately after modifying the theme.json color palette indicates a fatal JSON syntax error. JSON does not tolerate trailing commas, missing brackets, or unescaped characters. If you have a trailing comma after the last color object in your palette array, the entire file becomes invalid. Use an online JSON validator to correct the syntax.

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