**Steps to replicate the issue** (include links if applicable):
* Set user preference to "Client side MathJax rendering (for browsers with limited MathML support)"
* View the page https://en.wikipedia.org/wiki/Help:Displaying_a_formula
**What happens?**:
The following latex expressions fail.
* <math>\tilde{a}</math> gives "mover" red writing on yellow background
* <math>^\wedge</math> gives " msup" red writing on yellow background
* <math>f(n) =\begin{cases} n/2, & \text{if }n\text{ is even} \\3n+1, & \text{if }n\text{ is odd}
\end{cases}</math> "math input error"
* \boldsymbol{\alpha \beta \gamma \delta \epsilon \zeta \eta \theta} "math output error"
* \boldsymbol{\iota \kappa \lambda \mu \nu \xi \omicron \pi} "math output error"
* \boldsymbol{\rho \sigma \tau \upsilon \phi \chi \psi \omega} "math output error"
* \boldsymbol{\varepsilon\digamma\varkappa\varpi} "math output error"
* \boldsymbol{\varrho\varsigma\vartheta\varphi} "math output error"
* \text{if }n\text{ is even} "Math input error"
* a \text{ } b "Math input error"
* <math>( \nabla \times \mathbf{F} ) \cdot {\mathrm d}\mathbf{S} = \oint_{\partial S} \mathbf{F} \cdot {\mathrm d}\boldsymbol{\ell}</math> "math output error"
* <math>\oint_C \mathbf{B} \cdot {\mathrm d} \boldsymbol{\ell} = \mu_0 </math> "math output error"
* <chem>{C_\mathit{x}H_\mathit{y}} + \mathit{z}O2 -> {\mathit{x}CO2} + \frac{\mathit{y}}{2}H2O</chem> Failed to parse (syntax error): {\displaystyle \ce{{C_\mathit{x}H_\mathit{y}} + \mathit{z}O2 -> {\mathit{x}CO2} + \frac{\mathit{y}}{2}H2O}}
* <chem>\mu-Cl</chem> "Math output error"
* <chem>[Fe(\eta^5-C5H5)2]</chem> "Math output error"
* <chem>A ->[{}\atop x] B</chem> Failed to parse (syntax error): {\displaystyle \ce{A ->[{}\atop x] B}}
* <chem>A ->[{}\atop\ce{+H2O}] B</chem> Failed to parse (syntax error): {\displaystyle \ce{A ->[{}\atop\ce{+H2O}] B}}
* <math chem>\begin{align}\overbrace{\ce{2Fe3O4}}^{\text{magnetite}} + \ce{1/2 O2 ->}\ &{\color{Brown}\overbrace{\ce{3(\lambda{-}Fe2O3)}}^{\text{maghemite}}}\\ \underbrace{\ce{2Fe3O4}}_{\text{magnetite}} + \ce{1/2 O2 ->}\
{\color{Red}\underbrace{\ce{3(\alpha{-}Fe2O3)}}_{\text{hematite}}} \end{align}</math> Math output error
**What should have happened instead?**:
All equations rendered correctly
**Software version** (on `Special:Version` page; skip for WMF-hosted wikis like Wikipedia):
**Other information** (browser name/version, screenshots, etc.):
Google Chrome 128.0.6613.138 (Official Build) (64-bit) (cohort: Stable)