Does YOUR "About Firefox" not show the splash screen - like mine does not?
I was needing to confirm what version of Firefox I have today - I have it on 'auto-update' and assume it's the latest (Mac V85) but wanted to check. I went to the Firefox MenuItem and selected "About Firefox" - and GOT NO RESPONSE! I tried it multiple times to no avail.
The forum software identified your Firefox version as 85.0.2 and that would mean you have the current release. See also the "Help -> Troubleshooting Information" (about:support) page.
Note that Firefox 86.0 is scheduled for release next week Tuesday.