> At browser launch, Firefox will wait for uBO to be up and ready before network requests are fired from already opened tab(s).

> This is not the case with Chromium-based browsers, i.e. tracker/advertisement payloads may find their way into already opened tabs before uBO is up and ready in Chromium-based browsers, while these are properly filtered in Firefox.

Wow. I did not know this. This seems like a huge bug/problem in Chromium if you care about blocking trackers.