Github for Unity - commit button

Hi,

does anybody know, how to commit with the Github for Unity plugin?

In the documentation they say, you can simply click the commit button.
And on the appended image there is actually also a button.
But on my window (version 1.4.0 from asset store) there is only the text “commit to [branch]”. But this is no clickable Button. (see appended images for comparision)

Does anybody know, why that is not clickable, or even better, how to make it clickable?

Ok found the reason:

You MUST write something in the the commit summary and commit description fields, then the text becomes clickable