With the latest Photoshop update (21.2.2), the fix we had to get the pressure sensitivity back with the PSUserConfig.txt fix is no longer working.
This fix was necessary to work properly with a Pen Stylus on Windows, without using the Windows Ink features.
We are used to turn of Windows Ink systematicaly when using a Pen Tablet because it causes a lot of issues. (Wacom and other brands)
Why Windows Ink is not suitable
Windows Ink ON :
1-There is a 1 second delay with every new clic and drag before the cursor catches up with the stylus. It happens when dragging a window, using a slider to adjust a value (in photoshop or any other app), resizing a layer, and even when drawing. So the begining of each new stroke will freeze for 1 sec before catching up to the movement of the stylus. You can imagine the hell it can be when hatching, or doing fast repetitive movements/adjustements.
2-Certain applications, like Chrome for exemple, don't respond to the stylus for certain things. You can't move the chrome window around at all when windows ink is enabled. You can't drag and drop email in your inbox from one tab to another, some clics and double clics aren't registered at all ...etc.
3-Windows Pen & Stylus fonctionnalites are working against a fluid use of a Stylus. Especially the infamous "Press and hold" setting, that needs to be disabled systematically if you don't want this "mouse freezing blue circle of death" to appear each time you stop moving your hand for more than half of a second. (I suspect this functionnality to be responsible for the lag before each new stroke, even when you have it turned off)
4-Just while typing this post, I've discoverd a new issue. With Windows Ink enabled, it is impossible to select text by dragging over it with the stylus. I had to drop it and use my mouse each time I wanted to edit a sentence.
Windows Ink OFF:
1-Everything works perfectly.
2-Pressure sensitivity in Photoshop is gone, and need to be reactivated with PSUserConfig.
These are all the reasons (I can think of right now) why we have no choice but to disable Windows Ink, and use the WinTab alternative to get the pressure sensitivity back in Photoshop.
I hope you now understand why enabling Windows Ink is not a solution.
We had a solution, please do not take it away from us.
I'm assuming that everyone would love to use regular settings, and not to have to tamper with this kind of work around, but unfortunatly that is not possible.
Again, using WinTab is not a choice, it is essential for any serious workflow.
I'm currently paying for the full Adobe suite, and not being able to work properly is a big issue right now. Not knowing when this will be resolved is very worrisome.
PS: "Windows Ink" or "Pen and Touch" drivers on Windows, are currently pushing for touch and tablet functionnalities. These are cumbersome and unfit for any professional Stylus use.