Obscene CPU usage with Safari (Version 14.0 (15610.1.20.4, 15610) on Catalina

I was invited to the AppleSeed beta yesterday and have installed Safari Version 14.0 (15610.1.20.4, 15610) on Catalina (10.15.6) - unfortunately it seems to love CPU usage.

With only Safari open, with no websites and all extensions disabled, it consistently uses 100% of the CPU on my MacBook Pro. As you start to actually use Safari, this usage climbs.

With just two websites open (https://developer.apple.com/download/ and this page https://developer.apple.com/forums/create/question), Activity Monitor reports that Safari is using 1,196% CPU and the fans are going full speed.

Is anyone else using the Safari beta on Catalina experiencing the same?

I've just reported this via Feedback Assistant.
I have the same issue and also reported it yesterday. I hope, that there will be update soon because I did not find any info how to revert Safari to stable version, currently it is unusable.
Same here, basically unusable!

Same problem after update macOS to 10.15.6 with default safari 13.1.2
Same version here, at some point and without a lot of open tabs, it even passed the 500% cpu usage, which is insane.
Safari v14.0 (15610.1.23, 15610) - Problem fixed.👍
Same experience. And you can't downgrade to the released version.
Use Safari Technology Preview to avoid the problem.
https://developer.apple.com/safari/technology-preview/

I've had this problem for a while and was using Safari Technology Preview without issue but still tried to fix regular Safari. I think I figured it out: Try looking in ~/Library/Containers/Safari/Data/Library/Caches. Clearing out my caches seemed to have fixed MY problem. I suspect cryptomining (cryptojacking) malware disguised as cache files.

Hope this helps "someone" out there.

Obscene CPU usage with Safari (Version 14.0 (15610.1.20.4, 15610) on Catalina
 
 
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