1. I cast lantern's lift (lantern bearer's disturb side) from the graveyard targeting my repository skaab.
2. This put two cruel witness triggers on the stack
3. I put a land into my graveyard for the first one but the second one just showed a face down card I couldn't interact with so I clicked done as it's the only thing I could do.
4. Result was the pictured state where the triggers are still on the stack and I can't interact with anything.
5. As you can see, I had lethal in the air at the time meaning the bug cost me this game (game 3 of quick draft, currently 2-0).

Steps to Reproduce:

1. My opponent attacked me with a Voldaren Epicure among others.
2. I blocked the Epicure with my Kessig Wolfrider.
3. The opponent cast Sure Strike on their Epicure.
4. I cast Rending Flame on their Epicure in Response, which triggers my Cruel Witness.
5. The surveil interface from the Cruel Witness trigger shows a face-down card and cannot be interacted with (see Screenshot 1).
6. After clicking "Done", the game states "Illegal blocks. Try again" and does not advance, nor allow any interaction. Restarting Arena resumed the game.

Platform: Windows PC

Steps to Reproduce:

1. My opponent attacked me with a Voldaren Epicure among others.
2. I blocked the Epicure with my Kessig Wolfrider.
3. The opponent cast Sure Strike on their Epicure.
4. I cast Rending Flame on their Epicure in Response, which triggers my Cruel Witness.
5. The surveil interface from the Cruel Witness trigger shows a face-down card and cannot be interacted with (see Screenshot 1).
6. After clicking "Done", the game states "Illegal blocks. Try again" and does not advance, nor allow any interaction. Restarting Arena resumed the game.

Platform: Windows PC