Some anomaly in 3.1.1

[cebola2]

Issue Summary

Some macros fail in MathJax 3.1.1. Please compare

https://math.tecnico.ulisboa.pt/test.php (MathJax 3.1.0)

https://math.tecnico.ulisboa.pt/test2.php (MathJax 3.1.1)

[dpvc]

Oh dear! This is a serious regression. I'm pushing v3.1.2 as we speak to fix it. Thank you for reporting the problem so quickly.

[dpvc]

Version 3.1.2 has been published to npm, so should be hitting the CDNs soon.