All mixer and device panels opened at startup

Even though that this option is unchecked in Preferences, since yesterday all the mixer panels and devices are opened at startup. Is there another setting that could cause this?

Preference settings:


Startup screen:

I suspect the issue is that you’re closing those plug-in windows by clicking the X buttons in their title bars: unfortunately, because the VST audio engine is a separate process, Dorico doesn’t currently get told when you close one of those windows by clicking those buttons, so it thinks they’re still open. And because when you open a project, Dorico basically passes a load of data to the engine to tell it to restore its previous state, it doesn’t know whether or not you had those windows open or closed. If the little ‘e’ buttons in the VST Instruments rack in Play mode are set to be switched on, then it will tell the engine to open those windows. Next time you close your project, try making sure those ‘e’ buttons are switched off, and you should find the VST instrument windows don’t open.

Yes, I clicked those X buttons. I did it now as you suggested and Dorico opens with all the panels closed. Thanks for the tip, Daniel.