I edit the post and now I see a line below the post but the upper line is still black and solid, also when I hoover over any of both lines I don't see the edited date. What im missing there? Im not sure what i should be looking at to be honest.
There's also a grace period of around 10 minutes from time you created the post. Any edits made within this interval won't add the dashed line.
I could not remember how long that grace period was, thanks for the reminder.