FYI
Upon upgrading to 21.2.1 my MSIX package builds started failing during the signing process with an error indicating "No siguature was present in the subject". I am using a custom signing with a Digicert Keylocker based key. The failure also existed previously, however the messaging was quite different. Upgrading to 21.2.2 did not clear up this problem.
I know that this is an item for consideration longer term, so I'm not expecting it to work at present, just wanted to highlight that it now appears with different symptoms.
Thanks!