What are the default permissions of directories in home (Desktop, Downloads, etc.)

Best to run this:

sudo chmod -R a+rwX,o-w /home/$USER

All directories will be 775. All files will be 664 except those that were set as executable to begin with. $USER is your name which normally is a system variable.

echo $USER

This discusses one specific error, but also has the suggested defaults.

https://help.ubuntu.com/community/dmrcErrors

More info on permissions:

https://help.ubuntu.com/community/FilePermissions

Ubuntu Home directories were created with 755 permissions but will be dropped to 750 with 21.04, now to prevent new home directories from being readable by other users on the system.

sudo chmod -R a+rwX,o-rw /home/$USER

Example showing one file, default in 20.04, change to similar to 21.04 & change back:

fred@z170-focal-k:~$ touch temp.txt
fred@z170-focal-k:~$ ll *.txt
-rw-rw-r-- 1 fred fred     0 May 19 09:11 temp.txt
fred@z170-focal-k:~$ sudo chmod  sudo chmod -R a+rwX,o-rw /home/$USERa+rwX,o-rw /home/$USER/temp.txt
[sudo] password for fred: 
fred@z170-focal-k:~$ ll *.txtsudo chmod -R a+rwX,o-rw /home/$USER
-rw-rw---- 1 fred fred     0 May 19 09:11 temp.txt
fred@z170-focal-k:~$ sudo chmod  a+rwX,o-w /home/$USER/temp.txt
fred@z170-focal-k:~$ ll *.txt
-rw-rw-r-- 1 fred fred     0 May 19 09:11 temp.txt

sudo chmod -R a+rwX,o-rw /home/$USER

The default permissions for the home folder is 755 :) Run chmod again as last time.