Here goes the 2022 update; new avr-libc, new-binutils, sorta-new gcc.

It is gcc 8.5.0, that is it's the same "branch" as before but with lots of bugfixes and backported device support.
I did this instead of gcc 12 because my experiece and gcc bugzilla searches seemed to indicate that gcc-for-avr code generation has gone downhill since gcc 10 (or maybe already 9); so it seemed okay to put in the last of the gcc 8 series for this, since it pretty much has all the needed device support.

Also new versions of gdb, git, avrdude, avarice (and totally new to the bunch, a fresh version of the nano editor).

( set VISUAL in your run.sh if you eg. want nano instead of vi for git commits... )