Just making sure this isn't a misunderstanding: Roundabout signaling laws and conventions vary between countries, and in some countries you're supposed to signal your intent both entering and exiting the roundabout, while in some you only signal at the exit. I'm not sure about French conventions, but in some European countries (Germany, some Eastern European countries, probably others) indicating before the roundabout is actually illegal.

French conventions are to signal when you're exiting at the next exit.

I drive in Italy and Canada, the signaling is very different. In Italy you would signal left to indicato "entering", then signal right when about to leave.

In Canada you signal before entering, and signal right when you plan to exit right, left when left, nothing when going straight.

This assumption doesn't work for Italy wherte there are roundabouts with 5 or more roads involved.