I can't find 'find window'

[feelkyosh]

If I input Ctrl+ F or Ctrl+Shift+F, I cannot find any find window popup.
It seems the popup set as transparent. However, I cannot find any setup for transparent windows.
Where can I find window transparency setup?

[feelkyosh]

It's due to my monitor setup. I use 3 monitors including laptop(main) monitor.
I open PN2 3rd monitor and input Ctrl + F.
The search window was hidden between the main monitor and 3rd monitor boarder.
Thank you.