Just a note that I haven't seen any changes in this area through 14388 now, but I have noticed something quite strange that may be a clue: the Options page for the "other" Adblocker out there (not running concurrently) also has a major problem (in its case, nothing beyond the logo shows).
Aside from the obvious, they seem to have something in common, since they both have a problem while other extensions work fine (like Mouse Gestures and Translator).
Adblock for Edge fail to add subscription
Re: Adblock for Edge fail to add subscription
Just to update, the extension now works fine in 14390!
It's 0.9.4.0. Unless that's a new version, it was the Windows build that did it.
It's 0.9.4.0. Unless that's a new version, it was the Windows build that did it.