Undocumented math keywords break fontification of math content

[saf-dmitry]

Undocumented math keywords like (eq:foo) and \eqref{foo} defined in the markdown-mode-font-lock-keywords-math variable don't get properly fontified and break the fontification of math content.

Expected Behavior

Math keywords are fontified properly and don't break the fontification of math content in the buffer.

Actual Behavior

Math keywords don't get properly fontified and break the fontification of math content.

Steps to Reproduce

1. Enable math support in Markdown buffer
2. Write something like (eq:foo) $a$
3. See fontification of math broken

Backtrace

markdown-mode math support enabled
Error during redisplay: (jit-lock-function 1) signaled (void-variable markdown-markup-face)

Software Versions

• Markdown Mode: From Git on 2023-05-21
• Emacs: 28.2.1
• OS: macOS 10.15