The Chrome Reddit thread has filled up today with complaints from Google Chrome users who say they can't use the mouse middle button to open links in new tabs. Using the CTRL key and a click on links also doesn't work for some users.
The root cause of the issue was identified as Chrome's built-in popup blocker, which appears to act up in the presence of some extensions and trigger a pop-up warning, preventing the middle-click action and blocking the opening of a new tab.
The issue isn't new, being first reported to Google engineers last year, on December 30, but only a few users reported problems.
But today, for unknown reasons, the issues spread to countless other users who didn't have any problems before [1, 2, 3, 4].
Furthermore, the issue also extended to affect the controls of video players. Some users reported not being able to open videos in fullscreen mode or interact with various other video player buttons. YouTube videos were also affected [1, 2, 3, 4].
Complaints didn't only flood Chrome's official subreddit, but also social media sites like Twitter [1, 2, 3, 4, 5, 6, 7, 8], and Google's official help forum [1, 2, 3].
There haven't been any updates to Google Chrome since the official Chrome 71 release last month, so the issue doesn't reside in the browser itself. Answers from Google engineers have been confusing. Some said the problem was with the Chrome server-side popup blocker code, while other solely blamed extensions.
Chrome extensions known, at the time of writing, of causing problems with middle-clicks include Ghostery, DuckDuckGo Privacy Essentials, S3.Translator, ImTranslator, and RoboForm Password Manager. Other extensions may also block middle-clicks or video player controls, but they have not been publicly reported yet.
Users are advised to either disable Chrome's popup blocker from the browser's settings area at chrome://settings/content/popups, or disable all extensions and enable them one by one until they find the one blocking middle-clicks.
Other Chromium-based browsers weren't affected.
UPDATE: Shortly after this article went live, a Google Chrome community manager announced that the issue had been resolved.
"An automatic fix is rolling out over the next few hours," said Craig Tumblison, Chrome Community Manager. "No Chrome update is required, however you may need to restart Chrome to see the fix be applied once it is available to you."