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react/fixtures
Sebastian Markbåge 1506685f0e Suspensey Fonts for View Transition (#32031)
Fonts flickering in while loading can be disturbing to any transition
but especially View Transitions. Even if they don't cause layout thrash
- the paint thrash is bad enough. We might add Suspensey fonts to all
Transitions in the future but it's especially a no-brainer for View
Transitions.

We need to apply mutations to the DOM first to know whether that will
trigger new fonts to load. For general Suspensey fonts, we'd have to
revert the commit by applying mutations in reverse to return to the
previous state. For View Transitions, since a snapshot is already
frozen, we can freeze the screen while we're waiting for the font at no
extra cost. It does mean that the page isn't responsive during this time
but we should only block this for a short period anyway.

The timeout needs to be short enough that it doesn't cause too much of
an issue when it's a new load and slow, yet long enough that you have a
chance to load it. Otherwise we wait for no reason. The assumption here
is that you likely have either cached the font or preloaded it earlier -
or you're on an extremely fast connection. This case is for optimizing
the high end experience.

Before:


https://github.com/user-attachments/assets/e0acfffe-fa49-40d6-82c3-5b08760175fb

After:


https://github.com/user-attachments/assets/615a03d3-9d6b-4eb1-8bd5-182c4c37a628

Note that since the Navigation is blocked on the font now the browser
spinner shows up while the font is loading.
2025-01-09 10:33:44 -05:00
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