reflowing content inside MathML token elements

[dginev]

Sometimes a token element's content can horizontally overflow the current page width, especially when the page is styled with a maximum width. What is the right strategy for reflowing such elements? (especially <mn>)

If the overflowing text node was in regular HTML, one could use the CSS word-break property to induce a break. Currently that property doesn't successfully act on <mn> on either Firefox or Chrome. Here is a codepen demonstrating that:

https://codepen.io/dginev/pen/QWzVZNj

So I am opening an issue to ask:

• should word-break: break-all; be used in such situations?
• if not, what is a good mechanism to achieve reflow, specifically when the plain-text content of a token element exceeds the page width.

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Context: In a recent discussion of a web resource (namely computational discovery on jupyter ), I encountered an example which deposits an <mn> with 694 binary digits.

[dginev]

Determined in mathml-core meeting on Oct 30, 2023: This is a level-2 issue, which has lesser priority than the main reflow deliverable of level-2.

For the short term, there is a very useful workaround for Chrome - using a <span> child underneath any MathML token element that needs wrapping CSS to activate. Namely <mn><span>123...</span></mn>, successfully inherits and activates a rule such as

mn {
  word-break: break-all;
}