keyboard stops working in photoshop. Have to reactivate using mouse of F key.

I have a 2 screen setup on a mac pro 2019. There seems to be a bug that has driven me nuts for years. Each time I leave photoshop and come back I have to left click the screen with photoshop with the mouse before the keyboard works. Even if I click the photoshop icon in the dock, I then have to click the screen with the mouse. So when I am multi tasking and going between apps this is so annoying. No other app including no other adobe apps behave in this way so it is a photoshop bug. It has persisted through a number fo versions of photoshop and Mac operating systems, multiple Mac Pros and multiple keyboards and mice. I currently have Mac OS Big Sur and photoshop version 21.1.1. The only thing that hasn’t changed in the last 5 years is my Wacom intuos pro medium but I don’t use the Wacom mouse anymore. I use a Logitech M720 Triathlon. 

 

Sometimes while working in photoshop the keyboared stops working even without leaving the app. I have to then left click the photoshop screen followed by pressing F to take me through the next screen mode. (Don’t ask I have even came across that workaround) So each time I have to press F key 3 times to come back to the screen mode of choice again. This problem seems to occur a lot if I use the proerties panel. Sometimes it gets to the stage that each time i go the properties panel to make changes say to a curves adjustment layer the keyboard stops working after the edit. 

 

Has anyone experienced this and does anyone know how to resolve it.