[Fix] Theme boot script embeds storage key without script-context escaping#467
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mrubens merged 1 commit intoJul 17, 2026
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Apply CodeQL-recommended post-JSON.stringify escapes so the inline FOUC theme boot script cannot break out of a JavaScript/HTML script context.
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mrubens
marked this pull request as ready for review
July 17, 2026 04:16
mrubens
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daniel-lxs and
mrubens
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July 17, 2026 04:16
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What changed
The theme FOUC boot script now applies extra Unicode escapes after
JSON.stringifywhen embedding the personal theme storage key into the generated inline JavaScript. Unit tests cover script-breakout character escaping and that the embedded key still decodes to the intended localStorage key.Why this change was made
CodeQL alert #67 (
js/bad-code-sanitization) flags thatJSON.stringifyalone does not protect values interpolated into constructed JavaScript, especially against characters that can break out of an HTML/script embedding context. Hardening the embedding path closes the finding without relying on the storage key remaining a benign constant forever.Impact
No intended user-facing theme behavior change for light, dark, or system preferences. The change is security hardening on the web theme boot embedding path and should clear the open improper code sanitization finding once CodeQL rescans.