diagnostics jumps up and down on refresh

[adameat]

probably because skeleton height is less than actual content height.

@AlinaBelousovaUX do we actually need skeletons here on refresh? maybe silently replace with new values, as we do everywhere else?

UPD: make skeleton only for initial load

[astandrik]

@adameat couldn't reproduce problem
please check and confirm that problem persists

[astandrik]

fixed here #2801