Light, dark, and system themes
Three modes, switchable from the top bar or with Shift T, saved to your account so they follow you, and applied on the server so there is no flash of the wrong one.
By ToDidIt Product TeamUpdated
The picker is in the top bar, with a checkmark against the current choice. Shift T cycles light, dark and system without opening anything.
System follows your operating system rather than pinning a mode, so the app turns dark when your Mac or phone does. It is a real choice rather than the absence of one, so picking it sticks.
Twice, on purpose. It goes on your account, and it goes in a cookie on the device you changed it on.
The cookie is what lets the server apply the theme before any HTML reaches the browser, which is the whole reason it is a cookie rather than browser storage: no flash of the wrong theme while the page loads. The copy on your account is what survives to a device that has never seen you before, so signing in on a new laptop picks your theme up rather than starting from scratch.
One gap worth knowing: tabs that were already open when you change it keep their current theme until they next load.
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