Your comments

How?  Forget the question.  I just reinstalled 4.7.0 and found how to change the interface language; by using the 3-barred icon in the upper right-hand corner or on the right-hand side of the tabs bar.

It'd be nice to be able to change the interface to the former one and the options menu doesn't seem ..., well, forget this too, for I just found how to change to the classic interface.  And now that I know how to do this, the interface is switched back to the new, modern one.

Thanks for your response, for it forced me to check what the 3-barred icon is. I thought it was just a designer thing.