I'm rewriting this question since it was deleted in the latest T3 meltdown. My sympathies to the T3 team and everyone who lost their data - I lost 3 community points :[
I wrote some code in a custom module that includes a simple select field but when you try to hover over the options, they disappear and can't be selected.
This issue is only happens in the following situations:
Using Firefox browser - all other browsers are fine
T3 template - other templates work fine
Inside a custom module - The markup in the page content works fine
This is not a css issue - I matched the broken module's markup css with working markup in the page content
Can anyone else confirm???