Just upgraded to 2023.12 and my dashboard is super slow. Scrolling barely works. It seems to be worse on macOS+Safari then on Windows+Chrome, but it there on both.
I made this developer tools screenshot on windows+chrome. It keeps scrolling, and the numbers keeps going up.
Anyone else having this issue? I have already cleared my browser cache etc.
It only happens on the ‘Overview’ page, all others are snappy as ever, and no scrolling messages in the debug window.
I am having the same issue on Mac in Safari. Cleared browser cache. Disabled all safari plugins.
But no issues on Mac in Chrome.
i could reproduce the issue from a different windows+chrome PC where i had never logged into HA before. but unlike on safari, the dashboard was usable, at least for a while. but the console output was still full with ‘uncaught (in promise)’ stuff. like 30-40 per second.
but for now i downgraded to 2023.11.3 and that resolved the issue.
I think I have isolated the problem on my side.
I removed a history entity that displayed my ping. Every time I re-add it the UI just hangs.
i didnt have any of those. i did try to create an empty dashboard, and that did not have the issue. but i didnt isolate which item(s?) was causing the issue
Same here with chromium on Windows.
First i thought it is the new thermostat card when they are switched off, but i’m not sure.
I just checked it and in my case the new thermostat card produces high load in chromium, when thermostats are switched off (and the new card looks weird).
When my automation switches thermostat to on, cpu load goes down to 0.x %.
Have you posted a github issue?
i have not. the downgrade solved the issue for me at the moment, and too busy with other things right now.
Thanks for your contribution.
I use an old iPhone 7 to display a HA-dashboard.
Since 2023.12 it starts to get very hot everytime the thermostats are off. 
