twrp – Trying to (fast) boot: Error verifying the received boot.img

As described in this answer by @irfan-latif, I am trying to boot (without flashing) my Google Pixel 3a into TWRP via the following command:

fastboot boot twrp-3.5.2_9-0-sargo.img

This failed with the following messages:

Sending 'boot.img' (65536 KB)                      OKAY (  2.028s)
Booting                                            FAILED (remote: 'Error verifying the received boot.img: Invalid Parameter')
fastboot: error: Command failed

The only things I found on this topic are:

What caused the error, can it be resolved, and if so, how?

P.S. Further details:

$ adb --version
Android Debug Bridge version 1.0.41
Version 31.0.2-7242960
$ fastboot --version
fastboot version 31.0.2-7242960
  • I have unlocked the bootloader.
  • I also tried booting the LineageOS recovery which appears to work, but continues starting Android normally instead of TWRP:
$ fastboot -v boot lineage-18.1-20210608-recovery-sargo.img
Sending 'boot.img' (65536 KB)                      OKAY (  2.004s)
Booting                                            OKAY (  7.085s)
Finished. Total time: 9.156s