midueshen wrote:
This issue is only present in websites that do not provid their own fonts and depend on the system's. This is why I posted the issue here rather than in Firefox forum or something, because it is not even related to Firefox, since other browsers, specifically Chrome and Safari have the same issue.
But the system has several hundred fonts to choose from. It is the responsibility of web sites to choose which fonts they use. If you don't like the font that a web site is using, you will have to contact them and ask for a change. It's a website problem, not a system problem. That's why you see it in all web browsers but not in native apps. The native apps are using a different font.
You pointed out how the embedded links are using a different font. That's a good example. If you inspect Twitter's internal HTML code, you can see what fonts they are using for the text of a Tweet:
TwitterChirp, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif
But for a link or hashtag, these are their font selections:
Tahoma, Arial, sans-serif;
That's an obvious difference. However, there are additional details. The operating system does ultimately decide what font to use regardless of those specified settings. Arabic is a good example. The operating system isn't going to use a font that can't represent those Arabic characters. There is an internal font "cascade list" that is used to pick a font that can best represent the text being rendered. There may also be additional heuristics that go into how fonts are chosen. I'm not an expert on font usage. But sadly, I often seem to know more about them than people who write major apps. 😄
But ultimately, anyone displaying pre-styled text has a responsibility to choose how that text is rendered. As you can see from the hashtag example, there are always different options to choose from. Apple isn't going to make stylistic choices (well, sometimes they do, but it's a long story). It is really up to the developers of the web sites themselves to decide how they want the text to look.