Bug when trying to discard with Thoughtseize/Inquisition of Kozilek

Hi,
When casting Thoughtseize (also reproducible with Inquisition of Kozilek) targeting an opponent sometimes the card is shown/highlighted in the reveal window but cannot be confirmed/discarded. The opponent still has the card in hand after the interaction, while I (the caster) lose 2 life (as expected for Thoughtseize) and then the game goes on as nothing happened.

Here's the clip of the problem:
https://drive.google.com/file/d/1FomiiOlrWljRKgX4I4rtziZKf0zArpXS/view?usp=sharing

Start by reproducing the issue with Thoughtseize or Inquisition of Kozilek, using the linked clip as the expected interaction reference. Trace the reveal-window selection and confirmation flow for an opponent's hand; done means the selected card is discarded, the opponent's hand updates, and Thoughtseize still causes the caster to lose 2 life.

Written by the indexing model from the issue text.