Yes, these are correct and you can install them.
We had update sites for FOF and FEF for quite a few years but they were dormant. Instead of only pushing updates with new releases to our software we now provide updates through Joomla's Update page whenever we're fixing something that's moderately important but doesn't warrant a new release of all of our software.
FOF 3 is receiving its penultimate update, having moved to deprecated status on March 2nd, 2021. It's no longer used by our software. Some third party software may still be using it so we are not removing it. When it goes End of Life in December 31st, 2021 we will publish a final update which will be removing it from your sites. That's the same way Adobe handled the deprecation and removal of Flash. It seems to be the easiest way for users.
FEF had a bug which caused a lot of 404/403 errors to be logged due to incorrect preload hints for its CSS and JS. Even though nothing untoward happens to your site because of that we addressed it and published version 2.0.2 with that fix. Please install it, it will keep your hosting error logs much "cleaner", by omitting all those errors logged due to the wrong preload hints.
Nicholas K. Dionysopoulos
Lead Developer and Director
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