I’m not sure if I should laugh or cry but out of no particular reason that I understand, my WordPress installation has started to speak French to me! At least all controls/popup-texts in the text editor are no longer in English! I don’t know any french, but luckily I know most of these things already without actually having to read the labels. Like this “insert link” example:

(Update: I guess I could mention that this is a plain Debian Unstable installation, and most of the thing is still in English. It is just parts of the UI that went French.)