The first stage is complete: Firefox 3.2a1pre as of Wednesday’s nightly will expose such indeterminate checkboxes as what we internally call STATE_MIXED. There are still two work items left as far as we can see:

1. Expose an action name for a checkbox that is in this indeterminate state.
2. Make sure we fire STATECHANGE events for STATE_MIXED.

For action item 1, I’d like to call out to you guys to offer suggestions on what this action name should be. My initial idea is “toggle”. The reason is that we will never know whether the next state after clicking will be fully checked or fully unchecked. That always depends on the web site’s author to decide. That’s why I first thought of this neutral name.

Anybody got any better ideas, or even a suggestion derived from other such indeterminate, or tristate, checkboxes from operating systems? Post your ideas here or comment on the bug.