TOAD editor change/replace takes all CPU and 10's of minutes

I have a larger file I am editing - 20k+ lines. I notice that change and replace does not work in TOAD, I have to copy and paste the text to another editor. If I try to do a change and replace in the TOAD editor, it uses huge amounts of CPU and takes at least half an hour to complete.

Is that generally the workflow by the community, not to use TOAD for any substantial edits to SQL files? It just seems rather clunky to have to copy/paste it to VS Code or Notepad++. Are there any settings that can fix this?

I have also experienced similar issues. I started opening the scripts in Notepad++ and doing all such editing there.
I don't copy and paste. I always save the files, as sometimes I have to do "hard reset" to the Toad application.

As soon as I save the file in NP++, Toad asks if I want to reload and I do so.

P.S. If you always use one file as your SQL scratchpad, there is a simple way to start NP++ opening a list of files. You can add this file to the list