Trello change history: Users are experiencing reCaptcha errors while signing up

Trello.com signup was blocked by reCaptcha errors in a vendor-rated critical outage from 2024-09-12 02:08 UTC to 2024-09-12 03:28 UTC, lasting 1 h 20 min. Trello reported identifying the root cause and confirmed resolution, but did not describe the cause or fix.