if_single modifier doesn't apply to first other key pressed

[HifeFish]

Ubuntu 22.04, wayland input-remapper 2.0.0 9e04df7 python-evdev 1.4.0

I am mapping right control to:

if_single(key(Menu), hold(Control_R))

I want the key to act as Ctrl when combined with other keys and context menu otherwise.

Tapping Ctrl opens the context menu as expected. But if I hold Ctrl and then press A twice, the first time the letter "a" is typed and only the second time all text is selected.

I have experimented with timeouts, but there is no value that will reliably make both functions work for me.