Bundle Google Fonts into the older bundled themes

[garrett-eclipse]

Similar to #46169 & #36753 this request is to drop the use of Google Fonts for the bundled themes.

Following from a discussion in #core-privacy I'm opening this to move on the Google Fonts issue with Gutenberg.
Discussion - ​https://wordpress.slack.com/archives/C9695RJBW/p1549043771637800

There's two main concerns;
From a privacy standpoint Google Fonts tracks users collecting PII
From a performance standpoint the assets should be served locally to take advantage of modern font-loading optimization, etc. The cross-domain request slows down the site even with pre-fetching.

From an initial scan this affects all bundled themes starting with Twenty Fourteen, but may just affect ALL as I did a quick search.

[kjellr]

From an initial scan this affects all bundled themes starting with Twenty Fourteen, but may just affect ALL as I did a quick search.

Twenty Nineteen's font stack is entirely system fonts, so this should not be a concern there.

[ocean90]

Changing the fonts is no longer an option for the themes as it would change the theme's initial look and feel. Unlike for the block editor, users can easily change the theme to use one which doesn't use Google Fonts.

As mentioned above, Twenty Nineteen has already dropped Google Fonts. I suspect that future default themes will follow this lead.

[garrett-eclipse]

Replying to kjellr:

Twenty Nineteen's font stack is entirely system fonts, so this should not be a concern there.

Replying to ocean90:

As mentioned above, Twenty Nineteen has already dropped Google Fonts. I suspect that future default themes will follow this lead.

Thanks @kjellr & @ocean90 that's great news and happy to hear it's moved in that direction.

Replying to ocean90:

Changing the fonts is no longer an option for the themes as it would change the theme's initial look and feel. Unlike for the block editor, users can easily change the theme to use one which doesn't use Google Fonts.

I'm in complete agreement with you there @ocean90, we shouldn't be changing theme aesthetic on users. As the current option users can switch themes or dequeue the font.

During #core-privacy talks on the subject some ideas were presented with the predominant one being bundle the Google Fonts assets, including license, within the themes to remove the external resource while preserving aesthetic. As such I'm re-opening this for further discussion and changing the title to reflect this.

Aside from the above concept and the original concept of switching to a system font the other idea presented was a Customizer option to disable the fonts.

[westonruter]

For the performance concern, Google Fonts now supports font-display natively. For patch which implements this for the core themes, see #47282.

It turns out that Google Fonts serves a wide array of font files depending on the user agent making the request. Different browsers and operating systems get different font files that are tuned for their environments. I learned about this recently myself. If it weren't for this content negotiation then bundling woff2 font files would make sense to me.

[sabernhardt]

This ticket came first but #55985 has more discussion now, so I'm closing this as a duplicate. If you would like to add anything, please comment on #55985.