If you opened up Instagram on Thursday morning and couldn't do your normal vertical scroll routine, you're not alone.
The social media app tested a new feature that switched the Explore timeline to a horizontal, tap-based flow which users are more accustomed to with Instagram Stories.
Take a look in the video below from the account of a PhillyVoice staffer.
Unfortunately, Instagram's test of the horizontally scrolling timeline was deployed far more widely than intended, company head Adam Mosseri said in a tweet.
Rumors of a potential change first surfaced in October when Instagram released a much more limited test. It's not clear whether users would eventually be given a choice between horizontal and vertical timelines if the new feature progresses beyond the testing phase.
What is clear is that lots of people were completely thrown off and not amused by the test.
Since the side-swipe appears to be universally hated — granted, like most new features for just about anything — it's probably safe to expect this change will not become permanent in the immediate future.