Something has changed between FF 80.0 and 80.0.1! Aug 30 and Sept 03, 2020. Either a change to the code for uBlock Origin, or a change Yahoo made, that doesn't like uBlock now.
On Aug 30, 2020 I could access my contacts normally in Yahoo mail. Now on Sept 03, My contact list is grayed out, until I turn off uBlock, then my contact list appears normally! I STRONGLY suspect yahoo made changes, since the uBlock update preceded this problem!
It may also have to be Off to allow display some web flyers!

Bloquea sonidos y audios de páginas web

No longer works for intranet http servers even when on the whitelist! Research shows that this might now be a feature.

Worked pretty well but I absolutely do not understand why you would remove the individual blocker for every website in the latest update. I had to manually downgrade the plugin. Auto-Update=off

Don't like the new feature that takes away dynamic filtering to green list a site. Why should the developers care if we have "improper usage" (whatever that means) of dynamic filtering. The extension is on our computer, not yours. Also, what do you mean by "seeing way too many cases of improper usage of dynamic filtering . . ." How are you seeing anything? Are you spying on the usage of my own computer?
What I am seeing with this new feature is sites not coming up properly and I have to double-click "CTRL" anyway to get the site to work properly.
uBlock is a great extension, but it is slowly being ruined. Shouldn't be surprised - anything that is good and great eventually gets ruined. I understand the techie truism, "if you pay for technology, you are the customer, if you get it free, YOU are the product". Just thought uBlock was different. Ho-Hum, my bad.

Blocks Twitch modules, half of the page is not displayed. Who knows where else this addon will screw up

Debería de poder bloquear los anuncios de los buscadores, como bing o Google, pero por el resto de funciones, es el mejor adBlocker con diferencia.

Youtubeでチャンネル登録ができなくなる。
通知が表示されなくなる。

Did and extensive testing of uBlock after the new permissions. I also compared with the previous version. The conclusion: Previous versions of uBlock did NOT track your IP and/or device. This new version that request new permissions, DO use your host name and access your IP.

There has been a lot of speculations about this recently. I have no idea what happened with uBlock, so I choose not to go into that. I can, however, confirm that there is data mining going on with this version. What happens with the user information (IP address, Host information / Name and Device information) I have no way to know from the tests.

I have problem with rendering performance...

Good addon, but it uses a lot RAM and ruins my browsing experience because of it. (I usually have a lot of tabs open).

Nagy csalódás!