CKeditor 4.12.1 - how to fix IE 11 issue?

Question

CKEditor

Hello Forum,

I'm having a problem with CKEDITOR 4.12.1 and IE 11, more specifically, when clicking on Dropdown menu's like styles and paragraph,
they show up for a moment and then disappear. Everything works fine in Firefox.
this problem only occurs with modal windows
. What could be the problem. Yes, I know that IE sucks, but such requirements.

Answer 1

And then they disappear? https://ckeditor.com/ckeditor-4/demo/ (nothing disappears for me)
if not, then the problem is on your site, in crooked scripts, crooked forces