the notebookbar miss an horizontal separator line like the statusbar already has.
Steps to Reproduce:
1. start any notebookbar layout
no visual separator between notebookbar and the main page.
on bottom of the notebookbar there should be an horizontal line as separator. the statusbar has an horizontal line on top.
User Profile Reset: No
Created attachment 151803 [details]
notebookbar layout without horizontal line
in red I draw an horizontal line on the screenshot.
Can not confirm this on Windows builds of master/6.3.0alpha1+
Of course by default the rulers are enabled and h-ruler draws including a border between the ruler and the NB. Turning rulers off (Tools -> Advanced -> Expert configuratio: search for "ruler" and edit to toggle false) there is still an edge--soft 3D--visible to the NB frame.
Admittedly, it is not a hard edge like separator between h-scroll bar and the status bar. And I guess an os/DE theme could obscure the 3D edge. But is the hard edge really needed? Seems like a DE theme is being is being misapplied.
Work was done on bug 59329 for cleaning up the 3D edges, and this is similar to bug 57433--but that was deemed unproductive to pursue...
Created attachment 151812 [details]
clip of soft 3D border to NB present on Windows
in win7 it work very well. maybe in win10 id work too, but also the screenshots from https://www.libreoffice.org/discover/screenshots/ didn't show an separator in win10 tabbed layout.
sorry it work in master.