User level: Level 1 (4 points)Safari 27.0 and MacOS 15.8.1 not work with YouTube. I return Safari 18.9
[Re-Titled by Moderator]
Original Title: Trouble with YouTube.
Posted on Oct 28, 2026 7:22 AM
User level: Level 7 (27,833 points)Oct 28, 2026 7:43 AM in response to leonid956
If you are already on MacOS 15.8.1 I do not believe you can revert Safari back to Safari 18.9 which was a Ventura based version of Safari. Safari 26 was released with Sonoma and Safari 27 with Sequoia.
As a first step, I suggest clearing Safari cache & history, then shut down & restart your Mac. See if that fixes the problem.
If not, at least as an interim measure until Safari can be further diagnosed, I suggest switching to Firefox as your browser.
User level: Level 10 (99,154 points)Oct 28, 2026 8:08 AM in response to leonid956
YouTube videos work fine on our 2018 Mac mini running Sequoia 15.8.2 and Safari 27.2.
Update your MacBook Air to Sequoia 15.8.2 and Safari 27.2, then re-test YouTube.
What's new in the updates for macOS Sequoia 15 - Apple Support
Update to the latest version of Safari - Apple Support
Then if that doesn't help...? I suggest using EtreCheckPro to look for other issues.
Download and run the free version of EtreCheckPro, from > https://etrecheck.com/en/index.html
Then post back here with your Report, as per > How to use the Add Text Feature When Post… - Apple Community
Originally posted at discussions.apple.com/thread/256384588