Sorry for being off-topic, but since there are a lot of French people here this information may interest some. of you.
I’ve been using this layout for years and I absolutely love it. I couldn’t be happy on a computer without it:
http://www.dicomoche.net/kbdfrac.htm
alt gr+key to write the red characters. Doesn’t remove any character from the standard AZERTY layout.
(note the available æ, Æ, œ, and Œ that led me to create this topic Suggestion of a slight improvement regarding French search processing ("œ" and "æ" special characters) - #8)
I also used the Microsoft keyboard layout creator (a quite fantastic tool) to change a few things on my layout.
For example, if I do alt gr + <, it now writes the … character. Not useful on Discourse since it automatically converts more than two dots in this character, but useful in any text input that doesn’t do it (so, the vast majority).