The new beta telescope simulator causes a lot of CPU activity on my system - always one core pegged to the max. Switching the beta off didn’t stop the usage until the page had been reloaded. This is using FireFox under Linux Mint 22.3 on an AMD 7040 system.
Hi, and thanks for reporting this.
This is because the new Aladin Engine, used for the background images, has an infinite loop to redraw everything.
I’m currently working on replacing their engine with one built in-house, that won’t have this issue.