“Stylish” extension with 2M downloads banned for tracking every site visit
arstechnica.com
arstechnica.com
So, it's not really clear to me than anyone really wants a real review process created.
However, any extension which becomes popular instantly is put under pressure to sell to someone else who wants to do this type of nonsense. Of course, the extension author may not know which companies that want to buy their work want to viloate user privacy and which don't - they just have an offer to pay for their work. So, even the authors that sell aren't necessarily doing anything wrong (at least not intentionally).
And there doesn't really seem to be a way for browser vendors to alert users when ownership of an extension changes - they may not even know, and even if they did, it seems unlikely that most users would know what to do with that information.
There just doesn't seem to be anyone in this whole process that really has an incentive to make things better. It seems like the only reasonable advice is to avoid extensions or only use extensions from major companies - which is kinda sad advice.
This is precisely what Apple tried to do with the Safari Extensions Gallery, and they got pilloried for it.
The author used burp, but couldn't you also validate what is collected more explicitly by viewing the xpi contents for that add-on?