I am unable to resize a polygonal viewport using the egrips. Once I click on the polygonal viewport the egrips show up. When I click on one of the egrips they just disappear and the viewport is unselected. 

If I click on the egrips on a normal rectangular viewport I am able to resize it, I only have the problem with polygonal viewports.

I had this problem in version 2020 so I tried updating to 2022 and am still having the same problem.