It is common misconception that Manjaro Linux is the maintainer of your system.
Manjaro Linux provides the package you are using but you are the system administrator, how you apply them is on you.
Read more in → Update - error: failed retrieving file 'community.db' from
The pacman.conf was updated 2023-05-21T15:55:00Z to remove the deprecated community repo - see the above link.
There is always a message on the console informing if a <pkg>.conf.pacnew has been created.
The same messages can be found in pamac - use the lower right arrow button to see the output.
If in doubt run pacdiff with the -o argument - as this will simply list if any changes need to be addressed
pacdiff -o