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MACHINE TRANSLATION:
YouTube slows down in Safari on Mac 2019 (Sonoma). The video plays normally for the first 30 minutes, then the following type of lag begins: the video "frozes" for a few seconds (the sound continues to go), and then the video, as it were, "catches up" with the sound in accelerated playback. In the Google community, the issue is marked as a copy, no one says anything how to solve it. What to do? In other Chromium-based browsers, everything is fine. How to solve it, caches, cookie files were cleaned - there is no result...
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Your symptoms sound like those due to overheating. GoogleChrome is a known heat producer and resource hog, unlike other Chromium-based browsers.
Excessive internal heat can cause the processor to clock back, slowing operations.See this Apple article that outlines ways to reduce heating in Apple laptop computers:
Keep your Mac laptop within acceptable operating temperatures - Apple Support
Adding useless anti-virus, so-called "cleaning" apps, and VPNs will also increase temperatures and slow the computer
👉🏻 You have found the English-language version Apple’s user-to-user communities. If you can post in English, you will reach a far larger audience and get faster help, with far less chance of our making a translation error.
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