It works that way but not always. If you just do it that way, maybe it stays, however, again, that is not the sequence. Unfortunately, I did not save the screenshot where it showed, as you did with page ispection, that it had not saved the margins but only the padding.
Now I've fixed it and I'm moving on, however, it took me two days before I was able to figure out the problem and overcome it.
If you have time do some testing, mostly going from the backend editor to the frontend and back again, saving the values once with the frontend and then checking again on the backend, then changing the values on the backend and checking again if you find them the same on the frontend-I'm pretty sure you'll see the problem. Also, always check the values that it then generates starting from the laptop and ending at mobile portrait: even there I think I've seen that sometimes it saves them one way and sometimes it doesn't save them at all.
I'm sorry I can't be more precise, Toufiq, but for this thing (and similar ones) I've already lost a lot of time and need to finish the job.
I hope you will be able to replicate the problem, because it breaks a lot of boxes....