Les PDFs sont merveilleux: but why is Safari loading them in French?

When Safari downloads a regular file, progress is reported in its popup download pane in plain English. That’s fine. But every time that it downloads an Acrobat PDF for display inline using Adobe’s PDF Viewer plug-in, progress is displayed in French. Pourquoi?

acrofrench1

I noticed this some time ago, although I’m not sure exactly when. It was certainly prior to the release of Sierra last year, and it has remained the same ever since.

If I disable the Adobe PDF Viewer plug-in, in Safari’s Preferences, Safari’s built-in PDF viewer shows a different and purely graphical progress bar.

acrofrench2

But when I enable Adobe’s plug-in, it seems to think that I’m a couple of hundred miles south, on the other side of la Manche. Admittedly the plug-in dates from the initial release of Adobe Acrobat Pro DC, back in March 2015, but the iMac that I was using then wasn’t set up to use French as its primary language any more than this one is.

According to Adobe, my copy of Adobe Acrobat Pro DC is also bang up to date, admittedly on the ‘classic track’ which spares me from renting it. I’m surprised that means that its plug-in has required no updates at all in nearly two years, but checking Adobe’s website doesn’t offer me any either.

Needless to say, there are no accessible controls in the plug-in. So why does it want to talk to me in French? Perhaps this is a case for the famous Hercule Poirot?