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

Bug Fixes

• SAML Authentication requests and Metadata were not strictly encoded, causing some Identity Providers to not correctly process Service Provider initiated Authentication requests.
• When using GitHub Connect, the GHES license sync process sent information that was not required.
• When pushing to a Gist, an exception could be triggered during the post-receive hook.

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.
• 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