css - Why does whitespaces between characters / words are handled in other way as general whitespaces?

Question

I have create a font-subset for my two used fonts. But if I enter the browser and inspect a given H1-Tag which should only use this font, it shows that 2 Fonts are used, because one character is taken from an Fallback_Font Open Sans:

The exact HTML-Tag:

<strong class="headline1">Carservice Meisterwerkstatt</strong>

The CSS which is used (BTW: PT Sans use the same Font-Subsetting, so the next Fallback for those 5 Glyphs is OpenSans):

To determine the Subset I've used: glyphhanger http://localhost:3000 and added the output of it as whitelist to the following command:

glyphhanger --whitelist=U+A,U+20-23,U+25-29,U+2B-3B,U+3F-57,U+59,U+5A,U+5F,U+61-7D,U+A9,U+C4,U+D6,U+DC,U+E4,U+F6,U+FC,U+F002,U+F017,U+F0F1,U+F2B5,U+F2DC,U+F46D,U+F500,U+F530,U+F5E1,U+F63B,U+F7D9 --subset=Dosis-VariableFont_wght.ttf

What I do search for is a way to figure out, which 5 Glyphs are used from Open Sans. Is there a way to get this in the DEV-Console?

For testing purposes, I've changed the font to other font face to see immediately if there is used another font as fallback. But as you can see, even with Alfredo as Fallback it is not visible which 5 glyph's are using this fallback.

Answer 1

I've tried now to remove each single Character in Content-Part of the Tag inside of the Dev-Console... and checked when does the font-mixing appear. I figured out, that it appear only if I have 2 Characters with a whitespace in between: r M

But if I enter only a character (or word) with a whitespace in front of, or after the character, it doesn't happend. M even not like M .

I found that there are more than one simple space-character. There are many (see https://emptycharacter.com/ down on topic Unicode empty characters)

So it seems the issue at least is, that the Font-Subset doesn't have the needed Unicode included.

If anybody knows how to easily figure out which exact unicode the browser request to the font, you are very welcome to paste it here as comment)