I know there's a Lemmy bug where people editing their comment (not sure if it's every time, but often enough) makes the counter go up. So a thread with just one comment that was edited after posting will show as having two comments, if you see what I mean.
It's a bit annoying, not sure how high it is on the bugfix priority list though.
That makes sense. I noticed it doesn't show created vs edited time stamps. I had originally thought it was an issue with post/comment languages and user profile language filter settings.
On the website if you hover ago the "X minutes ago" text on a post or comment you do actually get both timestamps, so they're being saved somewhere and the backend should know it was an edit rather than a new post. But who knows how these things work. Certainly not me 🤷♀️