I recently upgraded to 8.1 and my installation seems to be mostly working except that when I refreshed my packages with pkgin today firefox broke with a message that libxul couldn't find libicui18n.so.64 (I'm on my phone now so all this is from memory).
I tried with a different version of firefox but no luck and I also got the same result when using pkg_add. I seem to have some icu package installed and firefox worked fine until today.
Another thing when switching to 8.1 is that during boot I get a warning that $mtoff isn't set up right. I tried searching for a reasonable value for it but with no luck.
I come from Linux-land so I'm new to all things BSD. Any suggestions to how to fix these problems will be appreciated ?