On a French keyboard layout (AZERTY), period is typed by holding shift and pressing the semicolon key. Since imv then receives the event Shift+period, binding <period> does not work, you have to bind <Shift+period>.

I don't know what the usual way to solve this is, but e.g. sxhkd has to query xkeyboard-config for the implicit modifiers: <https://github.com/baskerville/sxhkd/blob/b0923b6b3d5d85b1ff80a5bb286934b8721a7c08/src/types.c#L148>. I hope there's a simpler solution.