
We're seeing an accessibility problem with how Firefox keyboard navigation works with checkbox elements. The expected key to changed the checked state is spacebar:
https://www.w3.org/wiki/CheckBox#Keyboard_Interaction
However in Firefox, this rapidly cycles the checkbox state between checked and unchecked with just one spacebar press, which creates an accessibility problem for keyboard users (they're forced to use the enter key, which is unexpected).
Here's my test system info: