NOTE: Recommended to enable develeoper debugging and keep and eye on them (logs and/or on display). A) People who installs weeklies normally was not affected: Install Moodle bf919dd (31 March weekly). As far as you'll need to repeat this a number of times, it's recommended to save a copy of this installation. VERIFY: No errors happen on upgrade. The 4 tables do not exist (oauth2_issuer, oauth2_endpoint, oauth2_system_account, oauth2_user_field_mapping). Upgrade to Moodle bd99cb9 (7 April weekly). VERIFY: No errors happen on upgrade. The 4 tables are created (oauth2_*). Verify that "OAuth 2 Services" in admin shows some buttons ("create xxx service ...") and no error. Upgrade to HEAD of integration / master (this patch applied). VERIFY: No errors happen on upgrade. The 4 tables are created (oauth2_*). Verify that "OAuth 2 Services" in admin shows some buttons ("create xxx service ...") and no error. With the last 3 points working we verify that the new steps do not add any problem to a working site. B) People who installed an "incorrect" version of integration.git and was facing this bug: Install Moodle bf919dd (31 March weekly). Or restore it from backup created in prev. section. Nothing to verify, was done in A). Upgrade to Moodle 1e3aa70 (one of the bumps that caused the problem). VERIFY: No errors happen on upgrade. The 4 tables do not exist (oauth2_*). Upgrade to Moodle bd99cb9 (7 April weekly). VERIFY: No errors happen on upgrade. The 4 tables do not exist (oauth2_*). Verify that "OAuth 2 Services" in admin ends with error because the 4 tables are expected to exist and are missing. Upgrade to HEAD of integration / master (this patch applied). VERIFY: No errors happen on upgrade. The 4 tables are created (oauth2_*). Verify that "OAuth 2 Services" in admin shows some buttons ("create xxx service ...") and NO error. With the 3 last points working, the patch fixed the problem for sites that were missing the tables. That's all, ciao