Bug after 18.3 - Selectors are not valid anymore

In my workflow I’m downloading a PDF, and Internet Explorer asks if I want to ‘Open’ or ‘Save’ it.
My Click action used to click ‘Open’, but after the update to 2018.3.1 it doesn’t work.

When I try to make a new selector I can’t even select the ‘Open’ button (At the bottom of the page. This is a Internet Explorer pop-up).

Selector can’t select button:

Check it using UiExplorer. Try with other Frameworks as well.