Missing filter hits

Environment

• Browser and full version: Chrome 93.0.4577.63
• Extension using this toolkit: test-mv2
• Commit hash: 35978fd8

Steps to reproduce

1. Run the following in the context of the extension's background page:

EWE.subscriptions.add("https://testpages.adblockplus.org/en/abp-testcase-subscription.txt");
EWE.reporting.onFilterMatch.addListener(console.log);

2. Open the following test pages:
   • https://testpages.adblockplus.org/en/filters/element-hiding
   • https://testpages.adblockplus.org/en/filters/element-hiding-emulation
   • https://testpages.adblockplus.org/en/filters/webrtc
   • https://testpages.adblockplus.org/en/exceptions/element-hiding
   • https://testpages.adblockplus.org/en/exceptions/generichide
   • https://testpages.adblockplus.org/en/exceptions/sitekey

Actual behavior

The following filter hits are missing:

Page	Request	Type	Filter
filters/element-hiding	N/A	ELEMHIDE	any element hiding filters
filters/element-hiding-emulation	N/A	ELEMHIDE	any element hiding emulation filters
filters/webrtc	stun:example.com	WEBRTC	@@$webrtc,domain=testpages.adblockplus.org
exceptions/element-hiding	N/A	ELEMHIDE	testpages.adblockplus.org#@#.testcase-ehe
exceptions/generichide	N/A	ELEMHIDE	testpages.adblockplus.org##.ex-gh-specific
exceptions/sitekey	N/A	ELEMHIDE	testpages.adblockplus.org##.testcase-sitekey-eh

Expected behavior

The same filter hits are passed to the listener, as can be seen in the developer tools panel of Adblock Plus (i.e. none of the ones listed above are missing).

Further information

This list is likely incomplete, since I haven't gone through all test pages, and I haven't been able to manually reproduce all test cases.