WoW UI Help

Hi all,

Trying to import a UI from one of the UI’s submitted by a user on the WoW UI subreddit. It exists as a text file and I’ve tried copying it through the text box in edit mode. For some reason it doesn’t paste the entire string, it has a limit. Is there any way around this? It is difficult for me to explain the issue as I don’t know exactly what is going wrong. Any help would be appreciated.