I've noticed a glitch here:
What I did was:
- post a very short, speculative answer
- did some more research, came back later and provided a working example; edited my previous answer with summary like "expanded; yadda yadda.."
- followed up with a tiny edit with summary "more traceback clarity"
Edits 2 and 3 were collapsed into one (standard behaviour), but the edit summary from the substantial edit has been completely replaced with the fixup's, which doesn't look correct to me.