Footnotes are not horizontally scrollable, yet their CSS does not force `white-space: pre-wrap; word-wrap: break-word;`

Bug
1

At t/108791/5, after entering:

[^3]: `Mozilla.MozillaFirefoxNightly_146.2510.1421.0_x64__jag0gd4e3s9p2` demonstrates otherwise, per:

    ![image|690x375](upload://88Y4U0UBQ1chKfMRERPNeFt9uEs.png)

…I see:

image
image350×395 2.12 KB

It cannot be scrolled. I frequently encounter this:

With Footnotes included-in-core, I’ve reported to Bug, rather than t/84533.