Annoying general behavior: the width of the text-input-fields, when editing a node, can be up to 2X your screen's width / decentered
With the help of the adept question by @J.Reynolds

Might solve this issue: (did so for me)

Just change the administration theme a couple of times

This can be changed at Appearance >> Administration


To which you can navigate manually using the administrative overlay
Or to which you can arrive directly, by default, via www.Your-Website-Domain/#overlay=admin/appearance