Libreoffice widgets 17.04 Beta 1

Hi, I was playing around with Ubuntu Mate 17.04 Beta 1.
I do not really to whom address this problem in launchpad, so I post it here first.
It may be an Libreoffice error, maybe an Ubuntu error, maybe an Mate error.
The widgets in toolbars and dialogs are very big and chunky. Ok, that's only an optical thing, but in some cases they widgets getting unusable.
An example is the line width in draw. The widget is as big, that the content of the widget get no space.

I tried to install the different packages for GTK2, reinstall the GTK3 package for Libreoffice, but nothing changed.
So I installed an old 4.4 version of libreoffice and the widgets had the right size and the theme integration works flawless.

So is this a Libreoffice or an Ubuntu thing?