etcupdate extract 
etcupdate diff

rm -rf /usr/src/* 
rm -rf /usr/src/.*
git clone -b releng/13.1 --depth 1 https://git.freebsd.org/src.git /usr/src

cd /usr/src/ 
git pull
git branch --all

make -j4 buildworld 
make -j4 kernel     
shutdown -r now     
etcupdate -p        
cd /usr/src         
make installworld   
etcupdate -B        
shutdown -r now