Twenty Nineteen: "NonBreakingSpaceOverride" breaks "ch" CSS unit

[Andy Schmidt]

Took me a while to figure out why some of our columnar layouts were all broken and wrapping in odd places with the new theme. Turns out, the Twenty Nineteen theme prevents usage of the "ch" CSS unit, because it replies on your "NonBreakSpaceOverride" font.

In Chrome, Mobile Safari (and Edge/IE11), the ch width is calculated as TWICE the correct width vs. the native Hoefler font. In Firefox it renders identical.

On the other hand, the ex width is calculated slightly smaller (incl. Firefox, but NOT Mobile Safari), but that would be tolerable.

This sample page will render the FIRST set of DIVs precisely - the SECOND set of DIVs demonstrates the problem:

<html>
	<head>
		<style>
			@font-face {
			  font-family: 'NonBreakingSpaceOverride';
			  src: url(data:application/font-woff2;charset=utf-8;base64,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) format("woff2"), url(data:application/font-woff;charset=utf-8;base64,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) format("woff");
			}

			.hoefler {
				font-family: "Hoefler Text";
			}

			.nbspover {
				font-family: "NonBreakingSpaceOverride", "Hoefler Text";
			}
			
			.w20ch {
				width: 20ch;
				height: 1em;
				border: 1px solid red;
			}

			.w20ex {
				width: 20ex;
				height: 1em;
				border: 1px solid green;
			}
		</style>
	</head>
	<body>
		<div class="hoefler">
			<p>00000000000000000000</p>
			<p>xxxxxxxxxxxxxxxxxxxx</p>
			<div class="w20ch">&nbsp;</div>
			<div class="w20ex">&nbsp;</div>
		</div>
		<div class="nbspover">
			<p>00000000000000000000</p>
			<p>xxxxxxxxxxxxxxxxxxxx</p>
			<div class="w20ch">&nbsp;</div>
			<div class="w20ex">&nbsp;</div>
		</div>
	</body>
</html>

[poena]

Twenty Twenty also use the NonBreakingSpaceOverride. It was discussed during the development of the theme ​in this GitHub issue #347, but no solution was found.

[karmatosed]

I think this needs opinions and consideration at this point, so adding that keyword. We ideally need a consensus and that either is going to be to agree this is the way both themes do this or to fix both.

[karmatosed]

For now I would recommend that this is closed as this was also in another theme and to change this now seems to me like it would impact an existing theme(s) too much. I am more than happy for that to be countered though, that said we should be ok about closing and moving on with a decision.

[karmatosed]

I am going to follow through with closing this thank you everyone. We can always consider reopening. Thank you everyone for your collaboration.