He's just wrong though. Clicking anywhere on the bar immediately turns on the edit for me (and has for years).

So either debian is turning on some odd defaults (maybe? It's been a long time since I used debian with a DE).

Or... (and this is my guess) he mucked around running commands he didn't understand trying to fix his "solid color desktop" issue and broke it himeself. I'm very suspicious of the lack of anti-aliasing in his screenshots as well.