Xavier NX FileSystem to ReadOnly?

If anyone knows how to change the JETSON Xavier NX FileSystem to ReadOnly, please let me know.
The general way to apply “overlayroot” to Ubuntu remains RW and unchanged.
I also tried the JETSON-specific methods listed on the following four sites, but none of them succeeded.

here’s one similar discussion thread, Topic 78540 to enable overlayfs for Jetson platforms.

Thank you for your reply.
I’m already aware of Topic 78540 and some of the Topics listed in it, and I’m trying it out.
As a result, neither method solved the problem.
(For example, it can’t boot, or stays in RW mode)

I learned yesterday that JetPack was updated from 4.5.1 to 4.6, so I tried it after the update, but the results didn’t change.

By the way, RaspberryPie officially supports the Read-Only function in the Ubuntu distribution,
It seems that NVIDIA itself does not officially disclose information on support for the Read-Only function at JETSON. Is my perception correct?