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On desktop Chrome, `SharedArrayBuffer` has been only available to pages that are [cross-origin isolated](https://developer.chrome.com/blog/enabling-shared-array-buffer.md.txt#cross-origin-isolation) since Chrome 92. However, doing so requires loaded cross-origin resources to comply with certain rules (for example, served with a specific HTTP header such as `Cross-Origin-Resource-Policy`).

To make it easier for developers to enable cross-origin isolation, Chrome has been working to introduce new options to relax the requirements for cross-origin resources:

- `Cross-Origin-Embedder-Policy: credentialless`: [Load cross-origin resources without CORP headers using COEP: credentialless](https://developer.chrome.com/blog/coep-credentialless-origin-trial.md.txt)
- iframe credentialless: [Easily embed iframes in COEP environments](https://developer.chrome.com/blog/iframe-credentialless.md.txt)
- `Cross-Origin-Opener-Policy: restrict-properties`: [Secure popup interactions with restrict-properties](https://developer.chrome.com/blog/coop-restrict-properties.md.txt)

By incorporating these new options, we hope you will be able to enable cross-origin isolation with relaxed requirements without reducing the security level.

If your site relies on SharedArrayBuffer with [site isolation](https://www.chromium.org/Home/chromium-security/site-isolation/), we have been running a [deprecation trial](https://developer.chrome.com/docs/web-platform/origin-trials.md.txt#deprecation_trials) so your website can be exempted from the restrictions. This trial provides more time, given that it has taken time to define the specifications and implement them.

As the [ongoing deprecation trial](https://developer.chrome.com/origintrials#/view_trial/303992974847508481) is about to expire while we are still working on remaining solutions, the deprecation trial of `SharedArrayBuffer` on desktop will be extended until Chrome 124. You don't have to take any action if you are already registered for the ongoing trial.