Especially in last Autocad versions, it is very annoying to move the mouse through the model and viewing a sort of the pre-selection, highlight of many elements such as hatches.
Like this:
How to disable it?
Attention: you will disable the highlight for every kind of element (line etc.):
write SELECTIONPREVIEW and put it to 0 (zero).
That’s it.
to know more: Autodesk official page
Disclaimer: this is a fast guide, a tutorial, an how-to article that I personally wrote for you. Feel free to write here any kind of suggestion! It is helpful if you need to solve your problem, if you need a tip or if you are in trouble and you need an help!