webext-storage-cache

A caching library for Web Extensions (Chrome, Firefox, Safari) with support for expired cache clearing. Version 6.0.3 is the latest stable release, actively maintained by the author (fregante). It provides two main APIs: CachedValue for simple get/set operations, and CachedFunction for memoizing function calls automatically. The library requires the `storage` permission and optionally `alarms` for scheduled cache purging. It ships TypeScript types and works with both Manifest v2 and v3. The deprecated legacy API from v5 is still available via `webext-storage-cache/legacy.js`. Key differentiators from general Node.js caching libraries: it is specifically designed for browser extensions, uses `chrome.storage` under the hood, and handles cross-context caching (background, content scripts, popup).