`\coloneq` is not displaying as expected

[cmcisaac6]

Issue Summary

coloneq is not displaying as expected. It's definition by mathtools was updated in 2022.

Steps to Reproduce:

In the Mathjax demo, type the following:

$\require{mathtools}$
$A\coloneq B$

Expected output is that it is equivalent to \coloneqq i.e. it looks like :=

This can be seen in the equivalent LaTeX minimal example, for example shown here on Overleaf

Context

It seems that the mathtools package previously defined \coloneq as :-. But this was changed in 2022 due to clashing with another package See latex3/unicode-math#142 (comment) and the documentation in section 3.7.3 on CTAN for more details.

Technical details:

• MathJax Version: 3.2.3
• Client OS: Mac OS 14.3
• Browser: Chrome 133.0.6943.142 (Official Build) (arm64)

[dpvc]

Our current mathtools package predates the 2022 and 2024 changes to the actual TeX package, so don't have this updates, as you have discovered. This is corrected in mathjax/MathJax-src#1213 which will be part of the beta.8 release of v4.0 coming soon. It will include an option to select which of the two sets of names to use.