Comment # 6 on bug 1094753 from Tony Mechelynck

Moving the troublesome icon away on the user's HD as in comment #4 is a
workaround, not a fix. In particular it doesn't fix the problem for all other
openSUSE users who have just upgraded, or will be soon upgrading, to the newly
released openSUSE 15.0 as I did today.

In the distro's gvim 8.0.1568 with GTK3 GUI, I see the same thing as in comment
#0, and the "Help" icon on the toolbar is much bigger than the other icons,
creating the problem.

I don't have the problem in my own gvim 8.1.26 with GTK2 GUI (recompiled from
scratch using "make reconfig" after the upgrade), nor did I see it in the gvim
7.4.326 with GTK2 GUI which was distributed with openSUSE 42.3.

I call this a regression in openSUSE 15.0 compared to 42.3.

N.B. The OS ought to be openSUSE 15.0 but there isn't yet an entry for that.
I'll report this latter problem in a different bug.