Hm. Coworker mentioning German uses "wenn" for both "when" and "if". So that "It's not a matter of if, but when" Google translates as "Es ist nicht eine Frage der wenn, aber wenn"
Asking my friends Veronika and Volker, if this is true? Was it hard to grasp if vs when when you were learning English? Does "wenn" feel more like it's probably going to happen, or does it leave in the sense that it might not?
(Reminds me of the Spanish Para/Por differentiation, which is tough for many English speakers.)
Followup: my friend Tim found this link that explains some of it Looks like "Wenn nicht jetzt, wann dann?" covers it. Though I'm already bad enough with vowels, wenn/wann would drive me nuts. (Surprised Google Translate missed it)