Usage of window.MSStream preventing typescript upgrade

[dbkr]

We use window.MSStream in https://github.com/matrix-org/matrix-react-sdk/blob/develop/src/toasts/MobileGuideToast.ts#L33 which has been removed by typescript: microsoft/TypeScript-DOM-lib-generator#1029

There's no documentation of why we use this, so we need to either find something else if this isn't appropriate any more, or add it to our types.

[t-moennich]

@dbkr the MSStream check is a common workaround to prevent a false positive detection of IE11.
Microsoft used a silly hack to force websites to show there real look instead of an IE fallback back in 2014, after they improved the rendering on there Windows Phone OS.
See here for an article about it.

This is still somewhat valid, if a user really uses an Windows Phone OS in version 8.1+ nowadays.
But as this OS is more or less dead, I think it's safe to remove the additional check.

[UwUnyaa]

It could be possible to use an interface that extends window and defines the type of this value to keep the check in place if necessary.

I don't think that's the case though, as IE isn't in the supported list, and neither is Windows Phone.

[t3chguy]

I added this to the Window interface as part of the upgrade. https://github.com/matrix-org/matrix-react-sdk/blob/7033f8696ae2a82a1fe23eefff6e3bf33ecc4e95/src/@types/global.d.ts#L71

I don't think that's the case though, as IE isn't in the supported list, and neither is Windows Phone.

Yes, but this is used in the MobileGuideToast & permalink handling for mobile_guide - so has to work on more browsers.