Github App Installation Setup URL does not preserve state query parameter after reinstallation

[9M6]

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Bug

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Hello,

When a user reinstalls the application Github does not send back the query params to our server; this functionality was fine just few days ago.

We have a single Github App which the user can use to install throughout different organisations in our platform, but in this case when a user reinstalls (without uninstalling the app) github does not send back anymore any of the query params.

Any idea what changes the past few days?

Steps to replicate:

1. Install a github app
2. Reinstall a github app once more (the send time query params are not passed through)

Thanks.

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[tomadowley]

I have been having users experience the same issue over the last week, it seems to only affect users who are not part of any organisation.

[9M6]

I'm part of many orgs but still face the same issue.

[barry1cassidy]

Same for me. State doesn't get sent to the post installation URL even when installing for an organization.

[hopesmyth]

Happening for us also. Can confirm it was working last week. It looks like the state parameter does not get passed back to us and also seems that any PKCE parameters passed in are getting ignored (and therefore do not get validated during the oauth code exchange later).

Frustrating as these are important for preventing XSRF attacks!