Intro flow: consent, attention check, initial opinion on two issues (climate + education). Condition (treatment/control) and perspective taking now happen in the chat app, assigned per matched pair right after matching rather than per individual here — see chat/__init__.py.

Matching waitpage + perspective-taking (treatment only) + view partner response + live chat. Players are matched with someone who holds the opposite position on either of two issues (climate or education). Whichever issue they disagree on becomes the discussion topic; if they disagree on both, climate is used. Condition (treatment/control) is randomly assigned per matched PAIR, right after matching — not per individual beforehand — balanced by a running count of pairs assigned so far. Treatment pairs then each spend up to 5 minutes writing perspective- taking arguments about the matched issue; a wait page holds each partner until the other has also finished (or the 5-minute timeout releases them), before the chat begins. Players who aren't matched within the wait timeout are sent straight to a Prolific completion link for partial payment, skipping the chat and survey entirely.