I used to be able to put breakpoints in a running web plugin by using the developer menu in Safari. This has not worked for awhile, and does not work at all on Catalina. I know that this is a known issues, and I understand the general issue here. There have been previous discussions on the topic (see link below).
It has been quite awhile. Is there any plan to get this back online? Dev and Debugging using print statements is very limiting.