I don't think there's anything we can do about this: MediaWiki generates the correct MathML, it just happens to look suboptimal in browsers due to the extra space from \,. Basically, I'm saying that the rather exotic \overset{\,\prime}{x} should be written as \overset{\prime}{x} instead.

I can reproduce this in Chrome but not in Firefox.

Allow me to speculate: On https://de.wikipedia.org/wiki/Teilchen_im_Kasten#Normierung we see this formula

@Aarohisharma3 Can you ensure that the colon in <math>A{:}B</math> is translated to <mo lspace="0em" rspace="0em">:</mo> and rendered without spacing? While you're at it, you might also want to fix T401746.

The ::= operator from Backus–Naur form has the same problem, see e.g. https://en.wikipedia.org/w/index.php?title=Probabilistic_CTL&oldid=1273433286#PCTL_syntax

I don't fully understand what you excluded, but dewiki never uses numbers without a leading digit so while .99 (point nine nine) should be squashed, it's OK if {,}99 isn't.

On dewiki, it's common to use {,} as decimal seperator, e.g. 3{,}14. Support for that would be nice as well.

Interestingly, \tbinom{n}{k} works just fine.

A minimal example is <math>n=|C|</math>. There is too much space in the Firefox rendering after the first vertical bar. This can be fixed by wrapping the expression |C| inside a mrow element like https://temml.org/ does.

Another related bug: The "i=0" in <math>\min\limits_{i=0}</math> should be rendered below "min" but it's not.

A possibly related bug is that the "2" in <math>\sin \cos^2</math> or <math>\deg \cos^2</math> is not rendered as a superscript (i.e. I would expect to see "sin⁡ cos²" but it actually renders as "sin⁡ cos⁡2"). Again, "Invalid markup: Incorrect number of children for <msup/> tag" is printed to the Firefox console. Interestingly, <math>\sin^2 \cos^2</math> is rendered correctly as "sin⁡² cos²".

Besides <blockquote> elements, floating divs (e.g. images) in the same paragraph also trigger this problem: <math>A</math> implies <math>B</math> ocassionally. <div style="display:float">