No idea why, but the su module is back. BUT, as written in my last post (a few mn ago), I can run sudo but not su.
There is no reinstall on rpm-ostree. It is a more complexe method. Even removing is not trivial
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# ls -alZ /usr/share/selinux/targeted/default/active/modules/100/su
total 24K
drwx------. 2 root root system_u:object_r:usr_t:s0 33 Jan 1 1970 ./
drwx------. 419 root root system_u:object_r:usr_t:s0 12K Jan 1 1970 ../
-rw-------. 3 root root system_u:object_r:usr_t:s0 1.9K Jan 1 1970 cil
-rw-------. 835 root root system_u:object_r:usr_t:s0 3 Jan 1 1970 lang_ext
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