When the user is trying to change the comment formatting options, the drop-down is not changing the screen focus in Firefox but it does when we use Chrome and Edge.

Please refer to the video attached for both Firefox and Chrome.

The behavior in Firefox needs to be changed and should be similar to what Edge and Chrome behave as.

While checking on firefox we noticed the below warning in the browser's console logs. It looks related. Pasting below in case it is helpful

This site appears to use a scroll-linked positioning effect. This may not work well with asynchronous panning; see https://firefox-source-docs.mozilla.org/performance/scroll-linked_effects.html for further details and to join the discussion on related tools and features!