Black toolbar icons error o LibreOffice 5.1

After installing this new version this problem appeared. It didn’t existed in LibreOffice 5.0.4. The only plug-in I have is Zotero and I am on Linux/Ubuntu.

(sorry, I still don’t have enough points to post the image)

(edit: activated screenshot)

Possibly GTK3 issue. So little info means little response.


Look at Q64348 for a possible fix.