# RP21 — Part C: the window closes again
# mutation in internal/stacks/signup_block.go:
#   - '\treturn err == nil && now.Before(t)\n'
#   + '\treturn err == nil || now.Before(t) // RED-PROOF RP21\n'
# go test -run ^TestSignupBlock_TheWindowOpensAndCloses$ ./internal/stacks
# verdict: RED (assertion)
=== RUN   TestSignupBlock_TheWindowOpensAndCloses
    signup_block_test.go:87: the window passed but the block did not come back
--- FAIL: TestSignupBlock_TheWindowOpensAndCloses (0.00s)
