The 2.19 series release notes contain important changes in this release series.

Security Fixes

• Packages have been updated to the latest security versions.

Bug Fixes

• Graphs for some metrics in the Management Console 'Monitor' page were displaying data in the opposite ordering than expected.
• Site Admin users could encounter timeouts when attempting to impersonate accounts that were members of a large number of Organizations.
• Backups of GitHub Enterprise Server clusters could intermittently fail due to duplicated Gist repository references.
• Transient, non-fatal errors returned from external LDAP servers during team synchronization operations could cause the incorrect removal of team members.
• GitHub Apps were unable to modify GitHub Team memberships via the API.
• GrahpQL queries that referenced Organizations could run slowly and occasionally time out on a GitHub Enterprise Server instance that contained a large number of Organizations.
• Inviting users to a team could time out if the invitees weren't already members of that team's Organization.

Changes

• Background job queues have been re-ordered to reduce the chances of user-visible jobs being delayed on very busy instances.

Known Issues

• On a freshly set up GitHub Enterprise Server without any users, an attacker could create the first admin user.
• Custom firewall rules are not maintained during an upgrade.
• Git LFS tracked files uploaded through the web interface are incorrectly added directly to the repository.
• Issues cannot be closed if they contain a permalink to a blob in the same repository where the file path is longer than 255 characters.
• The Let's Encrypt certificate registration feature consistently fails following an update to the external API.
• When pushing to a gist, an exception could be triggered during the post-receive hook.
• When "Users can search GitHub.com" is enabled with GitHub Connect, issues in private and internal repositories are not included in GitHub.com search results.
• Security alerts are not reported when pushing to a repository on the command line. (updated 2020-06-23)

Thanks!

The GitHub Team