Document allowlisting still applied after URL changes

Environment

• Browser and full version: Chrome 93.0.4577.63
• Extension using this toolkit: test-mv2
• Commit hash: e44dde9d

Steps to reproduce

1. Load test extension.
2. Run the following:
   • EWE.filters.add("****")
   • EWE.filters.add("@@||youtube.com/watch?v=BYQ8S5xtY68$document")
3. Navigate to https://www.youtube.com/watch?v=BYQ8S5xtY68.
4. Click on one of the suggested videos below the player.
5. Reload the page (may require force reload due to caching).

Actual behavior

• After 3) No requests are blocked.
• After 4) No requests are blocked.
• After 5) All requests are blocked (only some are blocked without force reload).

Expected behavior

• After 3) No requests are blocked.
• After 4) All requests are blocked.
• After 5) All requests are blocked.

Further information

This issue was originally reported as https://gitlab.com/eyeo/adblockplus/abpui/adblockplusui/-/issues/1037 and may also affect other websites that don't cause page reloads when navigating between different pages.