688c24d44c
novel-bookmark.user.js was split out of manga-bookmark.user.js and lost four constants: CACHE_KEY, LASTCHECKED_KEY, LATEST_CHECK_THROTTLE_MS and LATEST_CHECK_BATCH. Every use sits behind a try/catch or a fire-and-forget promise, so the ReferenceErrors were swallowed: backgroundRefreshLatest() threw before its first fetch, and the local cache silently read empty and never persisted. The issue named the two throttle constants; the cache keys are the same lost lines and are fixed here too. Add a static guard over both scripts, since no behavioural test can see a swallowed ReferenceError.