Noticed on mangastream.com that an EHH-entry like
was not shown in the blockable items list as blocked (when it did before) and therefore a warning was shown on the site.
So I disabled all filter subscriptions to make sure there isn't a whitelist-entry somewhere and after reloading the page it picked the EHH-entry up and blocked it correctly.
After that I re-enabled every filter one by one and refreshed the page after each, but to my surprise the EHH-entry was still doing its work correctly now even with all filters active.
Restarting the browser confirmed my suspicion: With every filter list enabled, the EHH-entry didn't get recognized/blocked again for some reason.
Disabling the first few filters and reloading the page did the trick and it worked again without even a browser restart required.