Wikimore

Reported cases.

Vesion on Beta has development version, some cases may render correctly there, but not here https://en.wikipedia.beta.wmflabs.org/wiki/Extension:Math/Native_MathML/Reported_Cases

See Extension:Math/Native_MathML/Operators for complete set of operators

See Extension:Math/Native_MathML/Chemistry for problem with chemical formula.

Cases 1-9

Reported Phabricator bugs
Number	LaTex	Rendering	Notes
1a T377057 open	`\text{let}\ {n \to +\infty}`	$let n \to + \infty$ ${\text{let}}\ {n\to +\infty }$	Too much space around operators when used in limits in MathML mode. Spaces should appear in normal mode,
1b	`\lim_{n\to +\infty}\left(1+\frac 1n\right)^n`	$lim_{n \to + \infty} {(1 + \frac{1}{n})}^{n}$ $\lim _{n\to +\infty }\left(1+{\frac {1}{n}}\right)^{n}$	Spaces should not appear in a limit
2 T375935 Done	`\lim_{n \to +\infty}\frac{\sqrt{2\pi n} }{n!}\left(\frac{n}{e}\right)^n = 1`	$lim_{n \to + \infty} \frac{\sqrt{2 π n}}{n!} {(\frac{n}{e})}^{n} = 1$ $\lim _{n\to +\infty }{\frac {\sqrt {2\pi n}}{n!}}\left({\frac {n}{e}}\right)^{n}=1$	The factorial symbol ! should be upright, it is sloping in Clients-side mathjax mode.
3 T375907 Done	`\det(A)=\sum_{\sigma\in S_n} e(\sigma)\prod_{i=1}^n a_{i,\sigma_i}`	$det (A) = \sum_{σ \in S_{n}} e (σ) \prod_{i = 1}^{n} a_{i, σ_{i}}$ $\det(A)=\sum _{\sigma \in S_{n}}e(\sigma )\prod _{i=1}^{n}a_{i,\sigma _{i}}$	\sum_condition puts condition in the in wrong position in MathML and client-side MathJax modes
4a T375349 Done	`\textstyle \int\limits_{-N}^{N} e^x dx`	$\int_{- N}^{N} e^{x} d x$ $\textstyle \int \limits _{-N}^{N}e^{x}dx$	\int_a^b limits in incorrect position in MathML mode.
4b Done	`\textstyle \int_{-N}^{N} e^x dx`	$\int_{- N}^{N} e^{x} d x$ $\textstyle \int _{-N}^{N}e^{x}dx$
4c Done	`\displaystyle \int\limits_{-N}^{N} e^x dx`	$\int_{- N}^{N} e^{x} d x$ $\displaystyle \int \limits _{-N}^{N}e^{x}dx$
4d	`\displaystyle \int_{-N}^{N} e^x dx`	$\int_{- N}^{N} e^{x} d x$ $\displaystyle \int _{-N}^{N}e^{x}dx$
4e Done	`\int\limits_{1}^{3}\frac{e^3/x}{x^2}\, dx`	$\int_{1}^{3} \frac{e^{3} / x}{x^{2}} d x$ $\int \limits _{1}^{3}{\frac {e^{3}/x}{x^{2}}}\,dx$
4f	`\int_{1}^{3}\frac{e^3/x}{x^2}\, dx`	$\int_{1}^{3} \frac{e^{3} / x}{x^{2}} d x$ $\int _{1}^{3}{\frac {e^{3}/x}{x^{2}}}\,dx$
4h Done	`\int\limits_{1}^{3}\frac{\frac{e^3}{x} }{\frac{x^2}{5} }\, dx`	$\int_{1}^{3} \frac{\frac{e^{3}}{x}}{\frac{x^{2}}{5}} d x$ $\int \limits _{1}^{3}{\frac {\frac {e^{3}}{x}}{\frac {x^{2}}{5}}}\,dx$
4i	`\int_{1}^{3}\frac{\frac{e^3}{x} }{\frac{x^2}{5} }\, dx`	$\int_{1}^{3} \frac{\frac{e^{3}}{x}}{\frac{x^{2}}{5}} d x$ $\int _{1}^{3}{\frac {\frac {e^{3}}{x}}{\frac {x^{2}}{5}}}\,dx$
5a T375317 Done Works on beta	`\begin{align} \frac{dy}{du} &= f'(u) = e^u, \\ \frac{du}{dv} &= g'(v) = \cos v, \\ \frac{dv}{dx} &= h'(x) = 2x. \end{align}`	$\begin{matrix} \frac{d y}{d u} & = f^{'} (u) = e^{u}, \\ \frac{d u}{d v} & = g^{'} (v) = \cos v, \\ \frac{d v}{d x} & = h^{'} (x) = 2 x . \end{matrix}$ ${\begin{aligned}{\frac {dy}{du}}&=f'(u)=e^{u},\\{\frac {du}{dv}}&=g'(v)=\cos v,\\{\frac {dv}{dx}}&=h'(x)=2x.\end{aligned}}$	\align aligns fields in the centre rather that on the left in MathML mode
5b	`\begin{align} z & = a \\ f(x,y,z) & = x + y + z \end{align}`	$\begin{matrix} z & = a \\ f (x, y, z) & = x + y + z \end{matrix}$ ${\begin{aligned}z&=a\\f(x,y,z)&=x+y+z\end{aligned}}$
5c Done	`f(n) = \begin{cases} n/2, & \text{if }n\text{ is even} \\ 3n+1, & \text{if }n\text{ is odd} \end{cases}`	$f (n) = {\begin{matrix} n / 2, & if n is even \\ 3 n + 1, & if n is odd \end{matrix}$ $f(n)={\begin{cases}n/2,&{\text{if }}n{\text{ is even}}\\3n+1,&{\text{if }}n{\text{ is odd}}\end{cases}}$
5d Done	`\begin{align} a&=b & c&=d & e&=f\\ aa&=bb & cc&=dd & ee&=ff\\ aaa&=bbb & ccc&=ddd & eee&=fff \end{align}`	$\begin{matrix} a & = b & c & = d & e & = f \\ a a & = b b & c c & = d d & e e & = f f \\ a a a & = b b b & c c c & = d d d & e e e & = f f f \end{matrix}$ ${\begin{aligned}a&=b&c&=d&e&=f\\aa&=bb&cc&=dd&ee&=ff\\aaa&=bbb&ccc&=ddd&eee&=fff\end{aligned}}$
5e	`\begin{align} x&=y & X&=Y & a&=b+c\\ x'&=y' & X'&=Y' & a'&=b\\ x+x'&=y+y' & X+X'&=Y+Y' & a'b&=c'b \end{align}`	$\begin{matrix} x & = y & X & = Y & a & = b + c \\ x^{'} & = y^{'} & X^{'} & = Y^{'} & a^{'} & = b \\ x + x^{'} & = y + y^{'} & X + X^{'} & = Y + Y^{'} & a^{'} b & = c^{'} b \end{matrix}$ ${\begin{aligned}x&=y&X&=Y&a&=b+c\\x'&=y'&X'&=Y'&a'&=b\\x+x'&=y+y'&X+X'&=Y+Y'&a'b&=c'b\end{aligned}}$
6a T375295 Done	`\begin{align} \frac{dy}{du} &= f'(u) = e^u, \\[6pt] \frac{du}{dv} &= g'(v) = \cos v, \\[6pt] \frac{dv}{dx} &= h'(x) = 2x. \end{align}`	$\begin{matrix} \frac{d y}{d u} & = f^{'} (u) = e^{u}, \\ \frac{d u}{d v} & = g^{'} (v) = \cos v, \\ \frac{d v}{d x} & = h^{'} (x) = 2 x . \end{matrix}$ ${\begin{aligned}{\frac {dy}{du}}&=f'(u)=e^{u},\\[6pt]{\frac {du}{dv}}&=g'(v)=\cos v,\\[6pt]{\frac {dv}{dx}}&=h'(x)=2x.\end{aligned}}$	\begin{align} with font sizes specified show font size annotation [6pt] in MathML mode
6b	`\begin{align} \varpi &= [2,1,1,1,1,1,4,1,2,\ldots], \\[8mu] 2\varpi &= [5,4,10,2,1,2,3,29,\ldots], \\[5mu] \frac{\varpi}{2} &= [1,3,4,1,1,1,5,2,\ldots], \\[2mu] \frac{\varpi}{\pi} &= [0,1,5,21,3,4,14,\ldots]. \end{align}`	$\begin{matrix} ϖ & = [2, 1, 1, 1, 1, 1, 4, 1, 2, \dots], \\ 2 ϖ & = [5, 4, 10, 2, 1, 2, 3, 29, \dots], \\ \frac{ϖ}{2} & = [1, 3, 4, 1, 1, 1, 5, 2, \dots], \\ \frac{ϖ}{π} & = [0, 1, 5, 21, 3, 4, 14, \dots] . \end{matrix}$ ${\begin{aligned}\varpi &=[2,1,1,1,1,1,4,1,2,\ldots ],\\[8mu]2\varpi &=[5,4,10,2,1,2,3,29,\ldots ],\\[5mu]{\frac {\varpi }{2}}&=[1,3,4,1,1,1,5,2,\ldots ],\\[2mu]{\frac {\varpi }{\pi }}&=[0,1,5,21,3,4,14,\ldots ].\end{aligned}}$
7a T375861 reopened	`a\operatorname{sn}b`	$a sn b$ $a\operatorname {sn} b$	a\operatorname{sn}b rendered with no spaces before and after operator in MathML mode. Works in Firefox by not Chrome
7b	`a(\operatorname{sn}(b)), a[\operatorname{sn}[b]], a\{\operatorname{sn}\{b\}\}`	$a (sn (b)), a [sn [b]], a {sn {b}}$ $a(\operatorname {sn} (b)),a[\operatorname {sn} [b]],a\{\operatorname {sn} \{b\}\}$	no space need here
7c	`\operatorname{G}(V, g)`	$G (V, g)$ $\operatorname {G} (V,g)$	no space need here
8a T375907 Done	`\displaystyle\sum_{n\in\mathbb{Z} }`	$\sum_{n \in ℤ}$ $\displaystyle \sum _{n\in \mathbb {Z} }$	\sum_condition puts condition in the in wrong position in MathML and client-side MathJax modes
8b	`\displaystyle\prod_{n\in\mathbb{Z} }`	$\prod_{n \in ℤ}$ $\displaystyle \prod _{n\in \mathbb {Z} }$
8b	`\displaystyle\prod_{n\in\mathbb{Z} }^{n\ne 5}`	$\prod_{n \in ℤ}^{n \neq 5}$ $\displaystyle \prod _{n\in \mathbb {Z} }^{n\neq 5}$	with superscript rendered below
8c	`\sum_{n>k} R \quad \prod_{n>k} P \quad \coprod_{n>k} RR`	$\sum_{n > k} R \prod_{n > k} P \underset{n > k}{∐} R R$ $\sum _{n>k}R\quad \prod _{n>k}P\quad \coprod _{n>k}RR$
8d	`\bigcup_{n>k} J \quad \biguplus_{n>k} L \quad \bigcap_{n>k} N`	$⋃_{n > k} J ⨄_{n > k} L ⋂_{n > k} N$ $\bigcup _{n>k}J\quad \biguplus _{n>k}L\quad \bigcap _{n>k}N$
8e	`\bigoplus_{n>k} W \quad \bigotimes_{n>k} V \quad \bigodot_{n>k} F`	$⨁_{n > k} W ⨂_{n > k} V ⨀_{n > k} F$ $\bigoplus _{n>k}W\quad \bigotimes _{n>k}V\quad \bigodot _{n>k}F$
8f	`\bigvee_{n>k} V \quad \bigwedge_{n>k} W \quad \bigsqcup_{n>k} S`	$\underset{n > k}{⋁} V \underset{n > k}{⋀} W ⨆_{n > k} S$ $\bigvee _{n>k}V\quad \bigwedge _{n>k}W\quad \bigsqcup _{n>k}S$
8g	`\int_{n>k} U \quad \oint_{n>k} T \quad \iint_{n>k} S`	$\int_{n > k} U \oint_{n > k} T \iint_{n > k} S$ $\int _{n>k}U\quad \oint _{n>k}T\quad \iint _{n>k}S$	Default for integrals is to the side
8h	`\min_x\ \max_x\ \sup_x\ \inf_x\ \liminf_x`	$min_{x} max_{x} sup_{x} inf_{x} \underset{x}{lim inf}$ $\min _{x}\ \max _{x}\ \sup _{x}\ \inf _{x}\ \liminf _{x}$
8i	`\lim_x\ \varliminf_x\ \varlimsup_x\ \varinjlim_x\ \varprojlim_x\ \limsup_x\ \injlim_x\ \projlim_x`	$lim_{x} \underset{x}{\lim_{―}} \underset{x}{\lim^{―}} \underset{x}{\lim_{\to}} \underset{x}{\lim_{\leftarrow}} \underset{x}{lim sup} \underset{x}{inj lim} \underset{x}{proj lim}$ $\lim _{x}\ \varliminf _{x}\ \varlimsup _{x}\ \varinjlim _{x}\ \varprojlim _{x}\ \limsup _{x}\ \injlim _{x}\ \projlim _{x}$
8j	`\det_x\ \gcd_x\ \Pr_x`	$\underset{x}{det} \underset{x}{gcd} \underset{x}{Pr}$ $\det _{x}\ \gcd _{x}\ \Pr _{x}$
9a T375274 Done	`\arccot(x), \arccsc(x), \arcsec(x), \sen(x), \sgn(x)`	$arccot (x), arccsc (x), arcsec (x), sen (x), sgn (x)$ $\operatorname {arccot} (x),\operatorname {arccsc} (x),\operatorname {arcsec} (x),\operatorname {sen} (x),\operatorname {sgn} (x)$	mediawiki_function_names math functions eat the following paren in native MML mode
9b	`\arcsin(x), \sin(x)`	$\arcsin (x), \sin (x)$ $\arcsin(x),\sin(x)$
9c	`\operatorname{arccot}(x), \operatorname{arcsin}(x), \operatorname{sgn}(x), \operatorname{sin}(x)`	$arccot (x), arcsin (x), sgn (x), sin (x)$ $\operatorname {arccot} (x),\operatorname {arcsin} (x),\operatorname {sgn} (x),\operatorname {sin} (x)$

Cases 10-24

Reported Phabricator bugs
10a T375959 Done	`\langle \psi \| B^b \quad \lbrace \psi \| B^b \quad \lbrack \psi \| B^b`	$⟨ ψ \| B^{b} {ψ \| B^{b} [ψ \| B^{b}$ $\langle \psi \|B^{b}\quad \lbrace \psi \|B^{b}\quad \lbrack \psi \|B^{b}$	Use stretchy="false" for \langle and \rangle in MathML mode
10b	`B^b \|\psi\rangle \quad B^b \| \psi \rbrace \quad B^b \| \psi \rbrack \quad B^b \vert\psi\rangle`	$B^{b} \| ψ ⟩ B^{b} \| ψ} B^{b} \| ψ] B^{b} \| ψ ⟩$ $B^{b}\|\psi \rangle \quad B^{b}\|\psi \rbrace \quad B^{b}\|\psi \rbrack \quad B^{b}\vert \psi \rangle$
10c	`B^b \left\|\psi\right\rangle \quad \psi \left\|B^b\right\rangle`	$B^{b} \| ψ ⟩ ψ \| B^{b} ⟩$ $B^{b}\left\|\psi \right\rangle \quad \psi \left\|B^{b}\right\rangle$	Explicitly specifying \left and \right work
10d	`B^b \|\psi\rangle`	$B^{b} \| ψ ⟩$ $B^{b}\|\psi \rangle$
11a T375960 Partially done	`\updownarrow \big\updownarrow \Big\updownarrow \bigg\updownarrow \Bigg\updownarrow \dots \Bigg\Updownarrow \bigg\Updownarrow \Big\Updownarrow \big\Updownarrow \Updownarrow`	$↕ ↕ ↕ ↕ ↕ \dots ⇕ ⇕ ⇕ ⇕ ⇕$ $\updownarrow {\big \updownarrow }{\Big \updownarrow }{\bigg \updownarrow }{\Bigg \updownarrow }\dots {\Bigg \Updownarrow }{\bigg \Updownarrow }{\Big \Updownarrow }{\big \Updownarrow }\Updownarrow$	\Big/ and \Big\backslash etc are too small in MathML mode.
11b	`/ \big/ \Big/ \bigg/ \Bigg/ \dots \Bigg\backslash \bigg\backslash \Big\backslash \big\backslash \backslash`	$/ / / / / \dots \ \ \ \ ∖$ $/{\big /}{\Big /}{\bigg /}{\Bigg /}\dots {\Bigg \backslash }{\bigg \backslash }{\Big \backslash }{\big \backslash }\backslash$	Partially works in Firefox, upstream problems in chrome, some have almost zero use case
12a T375974 Done	`f:X\to Y`	$f : X \to Y$ $f:X\to Y$	Colon in f : X \to Y should be an operator in MathML mode.
12b	`D \And E`	$D & E$ $D\And E$	Has more space in LaTeX
12c	`A \smile B \frown B`	$A ⌣ B ⌢ B$ $A\smile B\frown B$
12d	`A \therefore B \because B`	$A ∴ B ∵ B$ $A\therefore B\because B$
12e	`B \overset{\underset{\mathrm{def} }{} }{=} B`	$B \overset{d e f}{=} B$ $B{\overset {\underset {\mathrm {def} }{}}{=}}B$
12f	`A \ulcorner B \urcorner B \llcorner B \lrcorner C`	$A ⌜ B ⌝ B ⌞ B ⌟ C$ $A\ulcorner B\urcorner B\llcorner B\lrcorner C$
12g	`A \blacktriangle B \blacktriangledown B`	$A ▴ B ▾ B$ $A\blacktriangle B\blacktriangledown B$
12h	`\forall(\ulcorner\phi\urcorner\in\Sigma^0_n\cup\Pi^0_n) \implies\mathrm{Tr}_n(\ulcorner\phi(y_0,\ldots,y_n)^*\urcorner))`	$\forall (⌜ ϕ ⌝ \in Σ_{n}^{0} \cup Π_{n}^{0}) ⟹ {T r}_{n} (⌜ ϕ (y_{0}, \dots, y_{n})^{} ⌝))$ $\forall (\ulcorner \phi \urcorner \in \Sigma _{n}^{0}\cup \Pi _{n}^{0})\implies \mathrm {Tr} _{n}(\ulcorner \phi (y_{0},\ldots ,y_{n})^{}\urcorner ))$	en:Reflection principle
13 T376546 Done	`\\|A\\|, D(p\\|q)`	$‖ A ‖, D (p ‖ q)$ $\\|A\\|,D(p\\|q)$	\\| should render as a double pipe \|\| rather than a single one \|. In MathML and Client-side MathJax modes.
14 T376558 Done	`q(v)=\|v\|^2\quad q(v)=\\|v\\|^2 \quad q(v)=\\|v\\|_A`	$q (v) = \| v \|^{2} q (v) = ‖ v ‖^{2} q (v) = ‖ v ‖_{A}$ $q(v)=\|v\|^{2}\quad q(v)=\\|v\\|^{2}\quad q(v)=\\|v\\|_{A}$	Vertical alignment of pipes with superscripts wrong in mathml mode
15 T376829 Done	`\cancel{y}`	$y$ ${\cancel {y}}$	\cancel{y} the strike is not visable in native mathml mode
16 T376838 Done	`\begin{array}{lcr} z & = & a \\ f(x,y,z) & = & x + y + z \end{array}`	$\begin{matrix} z & = & a \\ f (x, y, z) & = & x + y + z \end{matrix}$ ${\begin{array}{lcr}z&=&a\\f(x,y,z)&=&x+y+z\end{array}}$	\begin{array}{lcr} does not respect the optional alignment argument in MathML mode
17 T376883 open	`\frac{x}{x}\quad\frac{x}{y}\quad\frac{x}{l}\quad\frac{x}{2}\quad\frac{x}{x}\quad\frac{y}x\quad\frac{l}x\quad\frac{2}x`	$\frac{x}{x} \frac{x}{y} \frac{x}{l} \frac{x}{2} \frac{x}{x} \frac{y}{x} \frac{l}{x} \frac{2}{x}$ ${\frac {x}{x}}\quad {\frac {x}{y}}\quad {\frac {x}{l}}\quad {\frac {x}{2}}\quad {\frac {x}{x}}\quad {\frac {y}{x}}\quad {\frac {l}{x}}\quad {\frac {2}{x}}$	Bad spacing for fractions with Safari in MathML mode
18 T376887 Done	<math>\cfrac{x}{1 + \cfrac{\cancel{y}}{\cancel{y}}} = \cfrac{x}{2}</math> <math>\begin{array}{lcr} z & = & a \\ f(x,y,z) & = & x + y + z \end{array}</math>	MediaWiki MathML: $\frac{x}{1 + \frac{y}{y}} = \frac{x}{2}$ $\begin{matrix} z & = & a \\ f (x, y, z) & = & x + y + z \end{matrix}$ MathJax SVG: ${\cfrac {x}{1+{\cfrac {\cancel {y}}{\cancel {y}}}}}={\cfrac {x}{2}}$ ${\begin{array}{lcr}z&=&a\\f(x,y,z)&=&x+y+z\end{array}}$	Formula in separate paragraphs displayed on the same line in Safari on Mac OS in MathML mode
19a T377057 open	`\lim_{n\to +\infty}\left(1+\frac 1n\right)^n`	$lim_{n \to + \infty} {(1 + \frac{1}{n})}^{n}$ $\lim _{n\to +\infty }\left(1+{\frac {1}{n}}\right)^{n}$	Too much space around operators when used in limits in MathML mode
19b	`\text{let}\ {n \to +\infty}`	$let n \to + \infty$ ${\text{let}}\ {n\to +\infty }$	More space used when not in a script
20 T378433 Done	`\mathfrak{ABCDEFGHI}`	$𝔄 𝔅 ℭ 𝔇 𝔈 𝔉 𝔊 ℌ ℑ$ ${\mathfrak {ABCDEFGHI}}$	\mathfrak{ABCDEFGHI} appears as normal type in MathML mode on Chrome on Windows. Still broken for MathJax
21 T382672 Done	`{\bf Spec}, \bf A, \bf B, \bf C, \bf D, \bf E, \bf F, \bf G`	$𝐒 𝐩 𝐞 𝐜, 𝐀, 𝐁, 𝐂, 𝐃, 𝐄, 𝐅, 𝐆$ ${\bf {Spec}},{\bf {A,{\bf {B,{\bf {C,{\bf {D,{\bf {E,{\bf {F,{\bf {G}}}}}}}}}}}}}}$	Bold
22 T382716 open	`\det\nolimits^{\frac{1}{2} }`	${det}^{\frac{1}{2}}$ $\det \nolimits ^{\frac {1}{2}}$	Native MathMl rendering error in square root of the determinant
22 T382813	\begin{align} \int \limits_x A \\ \int \nolimits_x B \\ \operatorname{sn} \limits_x C \\ \operatorname{sn} \nolimits_x D \\ \operatorname{\int} \limits_x E \\ \displaystyle \sum \nolimits_n F \\ \displaystyle \sum \nolimits^n G \\ \operatorname{\Sigma} \limits_x H \\ \Sigma\limits_x I \end{align}	MathML $\begin{matrix} \int_{x} A \\ \int_{x} B \\ \underset{x}{sn} C \\ {sn}_{x} D \\ \int_{x} E \\ \sum_{n} F \\ \sum^{n} G \\ \underset{x}{Σ} H \\ \underset{x}{Σ} I \end{matrix}$ SVG Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. TeX parse error: \limits is allowed only on operators"): {\displaystyle {\begin{aligned}\int \limits _{x}A\\\int \nolimits _{x}B\\\operatorname {sn} \limits _{x}C\\\operatorname {sn} \nolimits _{x}D\\\operatorname {\int } \limits _{x}E\\\displaystyle \sum \nolimits _{n}F\\\displaystyle \sum \nolimits ^{n}G\\\operatorname {\Sigma } \limits _{x}H\\\Sigma \limits _{x}I\end{aligned}}}	native: Improve rendering for \limits and \nolimits
23 T382669 open	`\sum\nolimits_{n=1}^{\infty}`	$\sum_{n = 1}^{\infty}$ $\sum \nolimits _{n=1}^{\infty }$	\nolimits will be ignored on sums in displaystyle
24 T388304	`{n \choose k}`	$(\binom{n}{k})$ ${n \choose k}$	binomial coefficient
24 T388304	`{n \choose k}`	$(\binom{n}{k})$ ${n \choose k}$	binomial coefficient, using choose
24b	`\binom{n}{k}`	$(\binom{n}{k})$ ${\binom {n}{k}}$	binomial coefficient

New cases as of Aug 2025

Reported Phabricator bugs
Number	LaTex	Rendering	Notes
T375337 Done	`\frac{a}{b/2}`	$\frac{a}{b / 2}$ ${\frac {a}{b/2}}$	Too much space around / in MathML formatting mode
T375340 Done	`\binom{n}{k/2}`	$(\binom{n}{k / 2})$ ${\binom {n}{k/2}}$	Too much space between fences and content in MathML formatting mode
T375346 declined	`\begin{pmatrix} \begin{pmatrix}a&b\\ c&d\end{pmatrix} & \begin{pmatrix}e&f\\ g&h\end{pmatrix} \\ 0 & \begin{pmatrix}i&j\\ k&l\end{pmatrix} \end{pmatrix}`	$(\begin{matrix} (\begin{matrix} a & b \\ c & d \end{matrix}) & (\begin{matrix} e & f \\ g & h \end{matrix}) \\ 0 & (\begin{matrix} i & j \\ k & l \end{matrix}) \end{matrix})$ ${\begin{pmatrix}{\begin{pmatrix}a&b\\c&d\end{pmatrix}}&{\begin{pmatrix}e&f\\g&h\end{pmatrix}}\\0&{\begin{pmatrix}i&j\\k&l\end{pmatrix}}\end{pmatrix}}$	Lots of space around the cells in matrix evironments in MathML mode
T377167 Done	`\begin{array}{\|c\|c\|c\|} \hline a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ \hline a_{31} & a_{32} & a_{33} \\ \hline \end{array}`	$\begin{matrix} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33} \end{matrix}$ ${\begin{array}{\|c\|c\|c\|}\hline a_{11}&a_{12}&a_{13}\\a_{21}&a_{22}&a_{23}\\\hline a_{31}&a_{32}&a_{33}\\\hline \end{array}}$	Remove menclose in context of matrix representation
T378257 duplicate	`\operatorname{sn}\limits_x`	$\underset{x}{sn}$ $\operatorname {sn} \limits _{x}$	\limits is rendered verbatim in MathML mode and client-side MathJax
T379359 open	`\cancelto{x}{y}`	$y^{x}$ ${\cancelto {x}{y}}$	Fix \cancelto{y} in native MathML mode Chrome
T380184 Done	`\operatorname{vec}`	$vec$ $\operatorname {vec}$	$vec$ crashes with native MathML
T380654 reopened	`\begin{aligned}{\bar {X} }_{1}&=(X_{1,1}+\cdots +X_{1,n_{1} })/n_{1}\\[60pt]{\bar {X} }_{2}&=(X_{2,1}+\cdots +X_{2,n_{2} })/n_{2}\end{aligned}`	MathML $\begin{matrix} {\bar{X}}_{1} & = (X_{1, 1} + \dots + X_{1, n_{1}}) / n_{1} \\ {\bar{X}}_{2} & = (X_{2, 1} + \dots + X_{2, n_{2}}) / n_{2} \end{matrix}$ SVG ${\begin{aligned}{\bar {X}}_{1}&=(X_{1,1}+\cdots +X_{1,n_{1}})/n_{1}\\[60pt]{\bar {X}}_{2}&=(X_{2,1}+\cdots +X_{2,n_{2}})/n_{2}\end{aligned}}$	vertical space between multline equations is ignored. Dupe of T375295
T381102 Done	`\left(a\right)'`	$(a)$ $\left(a\right)'$	$(a)$ in MathML and MathJax renders with one prime symbol too much
T381305 duplicate	<blockquote>quote</blockquote>Let <math forcemathmode=native>n</math> be an integer Let <math>n</math> be an integer <div style="display: float">quote</div>.	MathML quote Let $n$ be an integer Let $n$ be an integer quote . SVG quote Let $n$ be an integer Let $n$ be an integer quote .	MathML/MathJax next to floating element or <blockquote> not rendered inline
T382196 Done	`\overbrace x`	$\overset{⏞}{x}$ $\overbrace {x}$	\overbrace rendered below (not above) in MathML and client-side Mathjax
T382215 Done	`a\ b \quad xy`	$a b x y$ $a\ b\quad xy$	TeX macro "\ " not inserting space in MathML and client-side MathJax
T384794 Done	`a' \operatorname{a}'`	$a^{'} a^{'}$ $a'\operatorname {a} '$	Prime symbol after \operatorname not rendered as superscript
T386071 Done	`_12`	$_{1} 2$ $_{1}2$	<math>_1</math> not rendered as subscript
T386318 Done	`\sin \cos^2`	$\sin \cos^{2}$ $\sin \cos ^{2}$	<math>\sin \cos^2</math> not rendered as superscript
T386585 Done T391889 dup	`\textrm{foobar}`	$foobar$ ${\textrm {foobar}}$	<math>\textrm{foobar}</math> results in "Math input error" with MathJax
T386787 Done	`\begin{bmatrix} 1 & 0 \\ \end{bmatrix}`	$[\begin{matrix} 1 & 0 \end{matrix}]$ ${\begin{bmatrix}1&0\\\end{bmatrix}}$	Trailing linebreak via `\\` in <math> matrix should be ignored
T387249 Done	`\hat{}`	$\hat{}$ ${\hat {}}$	<math>\hat{}</math> generates invalid MathML
T387952 Done	`{_{1}^2}`	$_{1}^{2}$ ${_{1}^{2}}$	<math>{_{1}^2}</math> not rendered as subscript
T389154 open	`\max_{D} \min_{A} \mathbb{E}`	$max_{D} min_{A} 𝔼$ $\max _{D}\min _{A}\mathbb {E}$	Not enough space around min and max in native MathML mode
T390259 reopened	`\mathbf{\Lambda}`	$𝜦$ $\mathbf {\Lambda }$	<math>\mathbf{\Lambda}</math> not bold
	`1\textbf{1}1 A\textbf{B}C`	$1 𝟏 1 A 𝐁 C$ $1{\textbf {1}}1A{\textbf {B}}C$	Also impacts numbers
T395489 open	`\xleftarrow{n+\mu-1} B \xrightarrow[T]{n\pm i-1} C`	$\overset{n + μ - 1}{\leftarrow} B \to_{T}^{n \pm i - 1} C$ $\xleftarrow {n+\mu -1} B{\xrightarrow[{T}]{n\pm i-1}}C$	Unreadable rendering of \xleftarrow with text in MathML mode
T397120 Done	`\textbf{1}`	$𝟏$ ${\textbf {1}}$	\textbf{1} renders incorrectly in MathML and client-side MathJax modes
T401623 open	`0.99`	$0.99$ $0.99$	Bad kerning of decimal separator in MathML
T401718 open	`\textstyle\sum_{i=0}^r \binom{m}{i}`	$\sum_{i = 0}^{r} (\binom{m}{i})$ $\textstyle \sum _{i=0}^{r}{\binom {m}{i}}$	\textstyle not applied to \binom in MathML
T401740 open	`\left\{ a \Bigg\vert \int \right\}`	${a \| \int}$ $\left\{a{\Bigg \vert }\int \right\}$	\Bigg\vert is not big in MathML
T401746 open	`x := 1`	$x := 1$ $x:=1$	Bad spacing of <math>x := 1</math> in MathML
T401849 open	`\mathrm{d}x`	$d x$ $\mathrm {d} x$	Too much space in <math>\mathrm{d}x</math> with MathML

New cases since Nov 2025

Reported Phabricator bugs
T410843	`p(a\|b)`	$p (a \| b)$ $p(a\|b)$	Too much space around a pipe symbol in MathML mode
T414276	`\{x\in\R : f(x)=0\}`	${x \in ℝ : f (x) = 0}$ $\{x\in \mathbb {R} :f(x)=0\}$	Not enough spacing before colon

Wikimore

Extension:Math/Native MathML/Reported Cases

Cases 1-9

Cases 10-24

New cases as of Aug 2025

New cases since Nov 2025