Today I downloaded the latest rolling release version from the website (2025.08.27-0019-rolling). Installing this image worked as expected without issues.
Consoling onto the device, I enabled ssh and created a user so I could copy and paste some commands onto the machine. The commit and save commands threw no errors, however the config.boot file is now empty

isaac.french@test-device# save
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isaac.french@test-device# cat /config/config.boot
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isaac.french@test-device# file /config/config.boot
/config/config.boot: empty
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isaac.french@test-device#

I was able to run the save command with an explicit path save /config/test.conf which worked. However, replacing the file was not possible

mv test.conf config.boot
mv: cannot move 'test.conf' to 'config.boot': Stale file handle
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It also could not be removed

sudo rm -rf /config/config.boot
rm: cannot remove '/config/config.boot': Stale file handle
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Rebooting the machine did not break it, and in fact it kept the configuration changes I had made, so this is not breaking anything as far as I can tell.
After rebooting the machine, I had all of the changes I saved before the reboot, and the config.boot file was re-populated. I assume something in the save functionality had broken and locked the file, but I could not see any process holding it open.

This was tested on a physical machine and a VM. Both were installed over and older image, and then re-flashed entirely with the issue occurring in each instance.