1. Reset all your key binds.
2. E. g. in the Helicopter page, add an additonal key bind to "Cyclic Left".
This works fine, it now shows a list of 4.
3. Afterwards, try to add an additional key bind to "Cyclic Right" (which is a separate filter preset of the same action).
Instead of adding it, it will replace all existing ones with the key.

I also ran into some issue where the config file had multiple entries for the same action, but I cannot remember how to reproduce that one.