Flutter actually controls every pixel that is drawn to the screen and doesn’t use HTML , JavaScript, or CSS to define any of its look or logic.
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Flash used the NPAPI to “break out” of the web and was basically “native” code you could escape to, whereas Flutter really is using web APIs, like Wasm, ARIA, WebGL, JS, WebComponents, and so on, to create true web apps that just happen to not use much of the control set that HTML exposes.
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