Ui scale Problems

My other toons/slaves share my 2 screen, and their UI scale is Big for some resason. But then i switch to them, the UI is normal again. But then the Main's Ui is bugged.

So The UI scale os only right in the One I has as main.

Anyone got the same problem? or have posted somthing like this before?

Can anyone help me here:s?
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Go into your chars and make sure you have the "Use UIScale" box checked or it won't work at all. That option got reset during the 4.0.x updates recently and unless you updated that setting manually, it is probably still disabled.