Implement facebook app secret proof

[mifi]

Initial checklist

• I understand this is a feature request and questions should be posted in the Community Forum
• I searched issues and couldn’t find anything (or linked relevant results below)

Problem

Facebook seems to require us to set «require app secret proof» button to be set to ON by june 11 2024. And when that s on, we need to send an app secret proof on every server request to facebook:

https://developers.facebook.com/docs/facebook-login/security/#appsecret

Solution

Implement app secret proof code in companion

Alternatives

Don’t implement anything and pray 🙏

[lakesare]

Thanks for creating this issue! I will add a few comments to clarify our situation.

Facebook makes it sound like app secret proof is optional in their docs, however, as we can see from the email they sent us, app secret proof is mandatory for any app that wants to go into production mode:

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So, in order to make uppy.io work,
AND, in general, to make any app that uses Uppy + Facebook in production work,
we will need to implement app secret proof support in Uppy.

[aduh95]

Fixed by #5249