I edit that by hand also to say buster
Yes, it is necessary to look at each sources file in sources.list.d and make appropriate changes to them where necessary.
once I get my chip backed up and copied to a new SD chip I will try the upgrade. I am waiting on some new SD chips it will be a week or so before I will actually be able try this. If Node-RED does not work I will back up my flows and reinstall Node-RED.
Just in case anyone else runs into this... and it is not related to raspi browsers for them - I have just had this symptom too: I was working on a flow on my laptop using firefox. I've now moved to my desktop PC, also using firefox, and all of a sudden I am importing and looking at my own flows, and all function nodes have this problem - they are opaque (you cannot see or edit the code) but they work. Bizarre.
Check for errors in the browser dev tools. Also try a ctrl-f5 to force a full reload (should ignore caching).
