* Remove prefetch boolean from JS sources - no reason to ever not use it
* JS optimization for header fetches on etag invalidation [#90]
* If promises are shared between requests, only the first invalidation makes the header request.
* If promises are not shared, simply delete the key.
* JS 3.0.3 [#90]
* update CHANGELOG
* replace compression-streams-polyfill with globalThis check [#167]
* work around web worker issue with decompression polyfill.
* js 2.10.0-beta.0
* js 2.10.0; update examples