After upgrade from OJS 2.4.8.1 to 3.1.0-1 editor noticed that one of editors forgotten to enter abstract in French language of submission that is published in French language. When we tried to enter abstract in French system always prompted that form was not submitted properly. I Noticed that whatever change was done in Title or Abstract fields the system reported that form was not submitted properly. I succeeded by changing everything except first letter and saved, after that deleted first letter. I guess that the field should not be left empty even if you copy paste into the filed new text i.e. title or abstract in French.