Most buttons on the toolbars have no labels in version 3.2. Not sure if this is considered a bug, but my previous version 2.6.19 did have labels below the buttons. On the MacOs version of GnuCash I cannot find a setting to enable them.
I suspect there is a GTK3 option to control this, but I haven't been able to find it with a quick look. Another, perhaps related, problem is that tooltips don't work right on the toolbar in the Mac version either. Sometimes they work ok, but most of the time they don't appear at all or perhaps appear for a fraction of a second and then disappear. I've found that if you mouse-down then drag a bit in the button the tooltip appears, so this is a work around of sorts.
I don't know what GTK3 is (I'm not a developer) and cannot find any settings for that. Tooltips do work, for me at least. Works as a work around, but breaks the fast work flow quite a lot. I hope it can be solved by someone.
Possible fix in PR383. Added a couple of preferences to govern icon size and how the toolbar items appear. I think this was also mentioned on the user list.
Bob's changes are pushed and will be in 3.3.
Unfortunately the proposed solution is not an acceptable fix so I have reverted this solution. I am motivating this in more detail here: https://github.com/Gnucash/gnucash/pull/383#issuecomment-408278377 The short term fix is to enable icons and text for all tool bar buttons (using small buttons due to limited space).
As a much needed gui overhaul is not planned in the short term we have decided to switch to small icons with text as a hard coded compromise starting with gnucash 3.3. Users not wanting the text can use a css snippet to hide this as documented on the Gtk3 wiki page: https://wiki.gnucash.org/wiki/GTK3#Sample_GnuCash_Selectors_.28CSS_Nodes.29
