The same thing happened to me less than two weeks ago:
In this case, I searched and found this thread but saw it isn’t in the GH category so my reply here would be invisible to the GH community. That’s why I created a new thread and copied my reply.
It’s very disconcerting to spend time working on GH code, only to find a thread missing. I’m not sure of the effect of merging threads in this case? Seems to me that duplicate threads (as is) are more likely to be found, eh? Thanks.