--userns-remap forces my bind mounts as slaves

Now that I enabled user namespace remapping, the bind mounts cannot be shared to other containers: Even though I specify the “shared” bind-propagation setting for my mounts the mount point inside the container becomes “shared,slave” (output of the findmnt -o PROPAGATION,TARGET).

if user namespace remapping is turned off the mount point is shared as expected.

I need to share the contents of this mount point to another container, while having the userns-remap feature on. How do I achieve this ?