Moodle 5.3, a long-term support (LTS) release, came out on 5 October 2026. That same day, an administrator upgrading from 5.2.3 posted in the Moodle community forums under the title “Upgrading to 5.3: middleware api authentication error”. The message named Moodle’s application programming interface (API) authentication middleware. However, the line underneath told a different story....










