Is this domain’s certificate valid?

Who issued it, and when it expires.

Try cloudflare.com, github.com. One domain in, one answer out. No account needed.
CONTINUOUS INTERNET TELEMETRY24H DRIFT7,537 material changesacross 5,803 domains · 24h to ~3h agoROTATION56 domains moved DNS from koaladns.com to magpiedns.com, 55 moved backa rotation loop, not a migration · 24hNOW562 curated domains not reachablelast probe, steadySITE ERRORS17,776 sites serving errorslast probe · 5xx / 404 / TLSBOT DEFENSEbot defense observed on 79,266 sites429 rate-limit / 403 bot-block, a posture signal