For instance, when I double-click photo thumbnails on the desktop, they do nothing, no matter how many times I click on them. Shouldn't they open in Preview? I have to right-click them and click 'open.'
Also, some third-party apps are slow and sometimes unresponsive. I've never had these problems before.
MacBook Pro 14″, macOS 26.0
For the double-clicking, check System Settings > Trackpad for the speed setting, try adjusting it.
It is possible there are processes running in the background that are using significant resources. Check Activity Monitor, CPU tab, sort by % CPU to see what's running hard.
Activity Monitor User Guide for Mac - Apple Support
See if the problem is present when you boot in safe mode, which disables 3rd party extensions and performs some system cleanup.
For the double-clicking, check System Settings > Trackpad for the speed setting, try adjusting it.
It is possible there are processes running in the background that are using significant resources. Check Activity Monitor, CPU tab, sort by % CPU to see what's running hard.
Activity Monitor User Guide for Mac - Apple Support
See if the problem is present when you boot in safe mode, which disables 3rd party extensions and performs some system cleanup.
Slow or unresponsive for certain tasks after Tahoe 26.0.1 upgrade
