Comment 122 for bug 1922342

I can confirm that "removing MBR partition 2" indeed WORKS.

I've tested the "second" step as I've already had booted from the stick a couple of times (and always had experienced the daunting delay).
Thus I've patched the partition on the stick directly as you've advised.

As expected the insanely long pause after hitting enter on the GRUB menu is gone.

Thank you for your investigation!

Incidentally, I'm assembling a new desktop system for me right now, it's a modern platform obviously... so I'm expecting all this to not be needed for it.