> The idea is I believe from French: maïs, Noël, etc.

Apropos of nothing, except that it will allow me to vent a bit, it also changes the rule for the pronunciation of the last consonant of French words.

Normally the lack of a trailing "e" would mean the last consonant is not-sounded but the diaeresis changes it: maïs/"my-isz", Noël/"noh-ell", etc.

And yes Moët (the champagne) is pronounced "moh-ett" in France and by French speakers.

It's incredibly annoying having someone subtly but in a slightly superior manner "correct" your pronunciation by repeating the mispronunciation right after you've pronounced it correctly - "sure, I'll order some some MOHAY". Outside I'm smiling and nodding pretending not to notice, inside I'm screaming "IT'S MOH-fcking-ETT MTHERF*KER - MOH-ETT."

> it also changes the rule for the pronunciation of the last consonant of French words.

This was a very well explained distinction, with the exception of you using "Noël" as one of the examples, since "Noel" would still have a sounded "L". It would be weird to a French speaker but would most likely end up being pronounced somewhat like the English "null".

> And yes Moët (the champagne) is pronounced "moh-ett" in France and by French speakers.

My favorite Moët mispronunciation is one that it took me several months to understand: Russians pronounce it as if it was spelled in Cyrillic, so they say "mah- yacht".

There is a famous MORGENSHTERN song which I only understood was about champagne when I saw the music video for the first time.