Reproduction Steps:
- Install an extension
- Open the console of its background page
- Execute the following:
(async ()=>{
console.log(await browser.runtime.getPlatformInfo());
})()
The platform information obtained from Orion is different to that obtained from Chrome in Macbook M1 Pro.
Orion vs Chrome

Firefox

As per Terminal's arch command in macOS, the architecture name shall be arm64
Version 0.99.126.3-beta (WebKit 618.1.2)
Build date Nov 20 2023
MacBook Pro (macOS Monterey 12.6.1 build 21G217)
The output of await browser.runtime.getPlatformInfo()) shall be the same as Chrome which is arm64
Version 0.99.126.3-beta (WebKit 618.1.2)
Monterey (12)
As it is executed as a chrome extension, the platform info shall follow the same as chrome