Usually when the worker is terminated it will also be completely destroyed/removed, which means that any global caches (such as the ones in `src/core/primitive.js`) should be automatically cleared in the process.
However, for certain ways of loading the `pdf.worker.js` file, e.g. passing in a re-usable worker to `getDocument`, using the `workerPort` functionality, or even disabling workers completely (even though this is never a good idea), the worker file may be kept in memory and these caches will not be cleared as expected.