YouTube has confirmed a display problem in its mobile apps for Android and iOS devices, where video thumbnails — the small images that preview videos — are no longer visible in the Home, Subscriptions, and Profile sections. Instead, users see empty boxes or rectangles. The issue was listed among YouTube's "known issues" and acknowledged on Sunday. According to a report, the platform marked the problem as resolved on Monday, September 28, with thumbnails and content expected to return to normal. However, if the issue continues, Google recommends users force stop the YouTube app and restart it. The bug affects both Android and iOS versions of the app and is specific to the mobile platform. The overall interface remains functional, with navigation bars and icons visible. However, when scrolling through feeds, users see gray, white, or black rectangles where thumbnails should appear. This issue also impacts other content types, including Posts and Shorts — short-form videos that are popular on the platform. A temporary fix suggested by YouTube is to update the app to the latest version through the Google Play Store or the App Store. Some users have reported that this action restored the thumbnails. Additionally, users with a YouTube channel should see a message on their home page titled "Known Issues on YouTube," which provides updates on ongoing problems. It is difficult to determine how many users were affected, as YouTube does not provide specific numbers. However, less than a day after the issue was reported, 160 users had mentioned the problem on the help forum. This number is likely a small fraction of the total affected users. One user speculated that thumbnails with unusual dimensions might have exposed previously hidden layout issues, but this remains a theory, as the bug affects multiple content types, and YouTube has not confirmed this explanation. The platform has assured users that it is working to restore normal service and will keep the discussion thread updated with new information.