All the time I edited my post it always shows like this but sometimes when I edit earlier or within a few minutes it doesn't show at all.
I can also see the changes when I login with a PC it doesn't even show at all untill I hover around the post then it comes up as the first user said.

If you're very observant you will likely notice a lot of little changes using mobile and PC, there are some changes that are not clearly visible except you attempt using a feature close to it then you will notice the minor differences.