Now my question is, how should I deal with these pacnew files?
Install pacman-contrib
which includes pacdiff
.
Meld is easy for beginners.
DIFFPROG="meld" pacdiff --sudo
See https://wiki.archlinux.org/title/Pacnew_files#Managing_.pac*_files for more options.
FYI:
ctrl
+shift
+t
brings back closed tabs.