Allowing additional { } seems like a good idea. Currently identifying what caused the problem, and fixing it can be a bit of a trial and error, sometimes you need { } around and expression, sometimes you don't.

One more https://en.wikipedia.org/w/index.php?title=Receptor%E2%80%93ligand_kinetics&diff=1307369112&oldid=1307366543

See https://en.wikipedia.beta.wmcloud.org/wiki/T402560

Some more coming through as pages are re-rendered.

I've fixed all the errors on English wikipedia. Mainly by removing { } and \atop.

https://en.wikipedia.org/wiki/Einsteinium has

\ce{ A ->[{}\atop x] B }

Checking formula on https://mhchem.github.io/MathJax-mhchem/

In T375317#11091487, @Christian1985 wrote:

Im not sure if the alignment in https://de.wikipedia.beta.wmcloud.org/wiki/Intbar#Algin should also be fixed. I think it is not fixed.

This is now working correctly on Firefox

Seems to be Firefox only. On Chrome, I get

This could be a chrome bug. On Firefox we have

This seems to impact numbers as well. For

Checked on Beta and MediaWiki. Not currently bold

Original example

BTW SVG rendering no longer seems to work on Beta.

I don't think this should be consider a duplicate of T375295. That task is really addressing not displaying the annotation, this is using that value.

See T375340 which looks at rendering of binomals in MathML.

Looks good to me.

That seems good.

Its a bit hacky but if we see

I'm pretty sure its not my browser set up. You need to get down to the Electrodynamics in media residing in curved space-times section.

I though as much, alas it is enough to block T271001 as rendering on many pages is substandard. Worse example I've seen is from https://en.wikipedia.org/wiki/Optical_metric

Even if the <math> tag is outside the <blockquote> we still get the same behaviour. The example

Example taken from https://en.wikipedia.org/wiki/Quotient_group#Even_and_odd_integers

Alternative like <math>\mathbf{a}</math> or <math>\mathbf{a1}</math> render fine.

We do have some test pages, one with the standard set of formula from Help:Formula

Tend to agree with Jacobolus that its not ready for prime time yet. There has been good work fixing the worse bugs but the rendering is still substandard.

It looks broken again

The \textrm syntax is not listed in Help:Formula so we could say that its not a supported syntax. We could probably add some rule so that \textrm is treated as \mathrm or possibly as \text. Either that or we treat it as an error and list it at Category:Articles with Maths Errors.

Also fails in Client Side MathJax mode.

Another example is mentioned in T389021 affecting the page

This looks like the same bug as T382267.

Original example

This is possibly related to T377657, but Blockquote is a more common case. The same bug occurs if either {{blockquote}} or <blockquote> is used.

See also T270348 with the same title.

The above is MathML rendering, just using the standard preference option.

But not in Chrome on Windows

Currently failing for

Currently at the top of https://en.wikipedia.org/wiki/User:Salix_alba/sandbox

The \ulcorner, \urcorner, \llcorner, \lrcorner don't have corresponding entries in the operator directory. So should probably be identifiers. Mainspace use at https://en.wikipedia.org/wiki/Reflection_principle where there should not be space

Going through the list of operators in Help:Equations the disparities are

\langle \psi | B^b \quad \lbrace \psi | B^b \quad \lbrack \psi | B^b fail
as do B^b |\psi\rangle \quad B^b | \psi \rbrace \quad B^b | \psi \rbrack \quad B^b \vert\psi\rangle.

We get the same for