It’s possible to fix a broken plugin by using debug to help you find the fault(s).

I have no use for that plugin so I don’t know of any others like it but I’d think there might be another answer.

Do give it a try if you wish. A backup of your site would be good to have just before proceeding and if it does break your site you should have a plan handy to get you into the plugins directory via FTP or your Control Panel’s file manager so you can rename that plugin’s directory name in order to kill it.

I tested it by installing the Classic Editor plugin. Then it was possible to use P5 again.