Like many Internet users, I’m not very fond of seeing ads all over the webpages I visit, so for years I have used extensions to block most of them. Last week I casually visited the ‘Extensions’ page in Chrome and discovered something very disturbing: AdBlock had enabled the checkbox ‘Allow in incognito’! The problem here is, I didn’t do that myself – I never enable extensions in incognito mode, since most of them can theoretically track every page you visit – so the extension must have did that by itself, without prompting me for permission nonetheless. Even worse, the checkbox is now disabled, so it’s impossible for me to revoke the access to incognito mode! I hide the toolbar button for most extensions, so if I didn’t visit the Extensions page that day I wouldn’t have noticed the change until much later.
After the initial surprise I started asking around to see if there’s an explanation for this. I checked my other versions of Chrome and in one the checkbox in ‘Extensions’ could be unchecked, so this looked like a bug. A couple of days later this was confirmed by both a Chrome developer and the people behind AdBlock’s Twitter account; they also created a support ticket for the issue. As far as I understand, the problem appeared because an update to AdBlock changed its behavior in incognito mode from ‘split’ (separate processes for regular and incognito windows) to ‘spanning’ (single process for extension, sharing data between regular and incognito windows).
@EXDE601E Hi, this is not our fault but Chrome's. Seems like bug, when "proxy" in manifest is enabled.— AdBlock (@getadblock) February 28, 2014
Unfortunately, two minor versions later the problem still persists, so personally I see no choice than removing this extension; I would rather see ads than be tracked by an extension who doesn’t have the decency to notify users of these kind of changes. A quick fix would have been trivial, just switch back to the ‘split’ incognito mode until Chrome or the own developers fix the bug. This lack of action doesn’t exactly inspire trust in their intentions…