This parameter works fine on 24.*.
I make “files“ directory in the 25.12.2 Image Builder root directory, and put my files, like /etc/config/network.
Then make image, with command:
MAKE \
PACKAGES="xxxxx xxxxx" \
FILES="files" \
ROOTFS_PARTSIZE="1024"
The ROOTFS size is correct, but the files I placed in the `files` folder are missing from the image?
openwrt-imagebuilder-25.12.2-x86-64.Linux-x86_64.tar.zst