Since https://github.com/Homebrew/brew/commit/0967c3e549d6f7fccff6412df1bca45efed101e4 , brew issues the following warning in Travis builds:
Warning: You are using macOS 10.11.
We (and Apple) do not provide support for this old version.
You will encounter build failures with some formulae.
Please create pull requests instead of asking for help on Homebrew’s GitHub,
Discourse, Twitter or IRC. You are responsible for resolving any issues you
experience, as you are running this old version.
(Judging by Which Releases of macOS Are Supported With Security Updates? and macos - What is Apple’s policy for supporting security updates on older versions of OS X? - Ask Different, this judgement comes from the observation that Apple only produces security patches for three most recent MacOS versions.)
Since Hombrew support is essential for most (if not all) projects using Travis MacOS environment, are you planning to react to this news in any way?