Mount android emulator vendor.img as read-write in Ubuntu

I want to poke a bit at a vendor.img file delivered as part of the android emulator system images. I am particulaly interested in Android 11 (API level 30).

I would like to mount it on a Ubuntu machine, modify it and then save it. With older versions (<= Android 9 (API level 28)), I can do this by mounting, modify and unmount it. But with Android 11 I get an error when I am mounting the image as rw.

These are the commands that I use:

$ fdisk -lu vendor.img
Disk vendor.img: 101 MiB, 105906176 bytes, 206848 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 5AE1C1A8-BAFF-4DE4-A85A-7A7093FA8019
Device Start End Sectors Size Type
vendor.img1 2048 204799 202752 99M Linux filesystem
$ sudo mount -t auto -o rw,loop,offset=$((2048*512)) vendor.img /mnt/vendor/
mount: /mnt/vendor: wrong fs type, bad option, bad superblock on /dev/loop17, missing codepage or helper program, or other error.

Mounting as ro works fine:

$ sudo mount -t auto -o ro,loop,offset=$((2048*512)) vendor.img /mnt/vendor/

But trying to remount it as rw doesn't:

$ sudo mount -o remount,rw /mnt/vendor/
mount: /mnt/vendor: cannot remount /dev/loop17 read-write, is write-protected.

How is this rw protection mechanism implemented, and how could I disable it?

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