When the window is smaller than the size of a toolbar, a >> arrow shows up, but when you open it up, it shows you a list of hidden and visible entries. It should only show the entries that are visible but currently hidden because of the limited screen size.
Created attachment 113747 [details] Kate's behavior when toolbar size is not sufficient for all items Kate is a text editor on Linux/KDE using Qt5. Another toolbar is added below the actual one that shows the hidden items
Created attachment 113748 [details] Behavior of Inkscape Inkscape shows a dropdown of hidden functions with the additional option to enable/disable it.
Created attachment 113749 [details] Toolbars on Firefox FF pops up a drowdown with the hidden links.
Created attachment 113752 [details] Kate with extended toolbar
KDE dev: "Kate's example shows the default behavior of Qt. There is no alternative like dropdown instead of the extended toolbar". My intention to ask was that we shouldn't override any system default, if not necessary.
Addendum: Kate/Qt transforms the wrapped toolbar into a dropdown menu in case there is no room to show one item http://wstaw.org/m/2015/02/27/kate.png (Processing is done internally on a very low level)
Component: ux-advise, so Status -> NEW
We're replacing our use of the 'ux-advise' component with a keyword: Component -> LibreOffice Add Keyword: needsUXEval [NinjaEdit]
Think the issue has been fixed. With 5.4.3.2. only the visible items are shown in the overflow menu.