Usage Exception: Linter 'versions' specifies invalid type 'libversion'. Available linters are: csharp, chmod, composer, filename, xhpast, csslint, gjslint, coffeelint, cppcheck, cpplint, flake8, golint, hlint, jshint, jsonlint, jscs, lessc, pep8, php, phpcs, puppet-lint, pyflakes, pylint, rubocop, ruby, generated, json, merge-conflict, nolint, phutil-library, script-and-regex, spelling, text, xml, checkstyle.

Not in comments either. Maybe I'm imagining it.

Ha! It's bad in the feed page.

Locally, I'm seeing it in comments in differential.

So feed and differential inline comments?

Regular comments, not inline comments (Although I haven't checked those yet).

So regular comments on the feed page, nothing to do with differential or inline comments?

Yeah, inlines too

maybe you can post screenshots so I don't have to guess what we're talking about.

Regular comments and inlines in differential, and records in Feed.
Does not reproduce in Maniphest.

Is this only on /feed/ or on other pages as well

inline:

Feed, from here:

Regular comment preview in differential:

And non-preview:

thanks, that clears it up for me!

MSIE behaves better:

Usage Exception: Linter 'versions' specifies invalid type 'libversion'. Available linters are: csharp, chmod, composer, filename, xhpast, csslint, gjslint, coffeelint, cppcheck, cpplint, flake8, golint, hlint, jshint, jsonlint, jscs, lessc, pep8, php, phpcs, puppet-lint, pyflakes, pylint, rubocop, ruby, generated, json, merge-conflict, nolint, phutil-library, script-and-regex, spelling, text, xml, checkstyle.