A remnant of acrylic looked like it would come in handy, but had a bent edge tall enough to collide with the laser nozzle. I eventually realized I could cut it with the edge downward, completely out of the way:
The supports are cardboard strips sliced from the cardboard stash with a razor knife and hand-bent specifically to avoid recursive yak shaving:
The cut was a simple straight line extending a bit beyond each end, using a bending mark to align the piece with the cut path. The scrap dropped free as the laser cleared the right end.
Nothing fancy, but it worked exactly right the first time.
Spam comments get trashed, so don’t bother; you’re not as clever as you think. Comment moderation may cause a delay.