If you use Color Sets in the Assets Catalog to define your color palette, make sure you enable variants for the Any, Light and Dark appearances and also High Contrast. You'll be able to define variations of the color that have better contrast.

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You can enable the possibility of providing assets for different appearances including light/dark modes and high contrast. As we've seen, that's valid for colors, but you can do the same for images too! https://x.com/dadederk/status/1594724075590619138?s=20&t=XJrlJiGSCTR9sJC7XPZPjA
@NSSpain has a great history of having amazing accessibility talks in their schedule! “Accessibility in the Real World”, by @Sommer: https://vimeo.com/235317172 “How to build an app for everyone”, by @NovallSwift: https://vimeo.com/362163043 The super fun "Choose your own SwiftUI adventure - 3 Accessibility", by @twostraws and @PinkerStraws: https://vimeo.com/481768105 And, of course, this year's great "Bas: My Accessibility Story", by @basthomas: https://vimeo.com/751176747

If you need to send announcement notifications that can step into each other, they will by default, interrupt ongoing announcements. But you can pass attributed strings as parameters too, letting you specify announcements to be queued.