firefox.exe --version on Windows prints the version string but may
return non-zero exit code (sub-process fork quirk). The previous check
treated that as a launch failure, producing a false-positive failure
across the whole matrix while the binary actually launched cleanly.
Switch to matching the printed output instead, so we only fail when the
binary really can't start.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
feder-cr
62b9030d2a