horizontal spacing for displayed equation structures when a floated element exists on the same line (version 4 beta 7)

Issue Summary

There is something wrong with horizontal spacing for displayed equation structures when a floated element exists on the same line. I have a page which is a kind of torture test on this respect.

Steps to Reproduce:

Go to https://mr.math.tecnico.ulisboa.pt/seminars_1?id=7380 on a tablet in vertical mode. You will probably see something like this

https://photos.app.goo.gl/5uY6UQs9G38vVwsXA

There is a displayed equation block missing between the words "form" and "where".

On a phone you might see it or not. I have not been able to make it reproducible but when you do see it it will look all right except for some extra vertical spacing after the displayed equation block as in

https://photos.app.goo.gl/JhR5o1jXf2v1GjbUA

On a desktop system there are no visible problems.

It might be relevant or not that the displayed equation block has an equation number.

Technical details:

This seems quite independent from browsers and other technical details except for screen width and MathJax version which is MathJax-4.0.0-beta.7 installed locally.

Configuration is available from https://mr.math.tecnico.ulisboa.pt/seminars_1?id=7380

Supporting information:

Start by reproducing the report at the linked seminar page with MathJax 4.0.0-beta.7 on a narrow tablet or phone viewport, comparing the displayed equation near “form” and “where” with desktop rendering. Investigate the displayed-equation behavior when a floated element shares the line; done means the equation remains visible and its horizontal and vertical spacing is correct across the reported narrow widths.