During my tests about IMA/EVM read that is recommended to use the
"rootflags=i_version" during the boot process.  Any change in the rootflags
breaks the boot during the sysroot mount and launch the emergency shell (if
configured to do so)

Reading the logs seems that the reason is maybe related with the snapper dracut
plugin, as dracut resolved the kernel command line as "... rootfstype=btrfs
rootflags=rw,realtime,space_cache,subvolid-267,subvol=/@/.snapshots/1/...
BOOT_IMAGE=... root=... .... rootflags=i_version"

The rootflags parameter is duplicated, and maybe should be merged.