When opening the Module workshop window from the top bar repeatedly it adds another header each time you click the button. There is no real impact in usability or performance at all, just a minor inconvenience.
It is quite easy to reset, simply close and re-open the window.
The other windows like the control panel work just fine.
I discovered this on CCK 3.1 build 82 on unity 2019.4.31f1
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