Is it possible to read URL parameters in Confluence Forge?

Is it possible to read URL parameters in Confluence with a Forge app?

I have an application that will require the user to provide authorization to use their account for the Adobe Sign API to send documents out for Signature as them. I have a custom endpoint that I own elsewhere to handle the OAuth redirect and would like to have that endpoint send them back to the page they were on and pass a URL state parameter to Confluence so I can immediately process the results of that authorization in Confluence.

I know I can’t use JavaScript to get the URL parameter and I don’t care to be able to edit the URL or URL parameter, I just want to be able to read custom URL parameters to pass and obtain state information on redirect.

Alternatively, if I POST the redirect to the Confluence page, is there anyway to access POST data so I can POST the state information instead of putting it in the URL?

Is it possible for you to use External Auth? https://developer.atlassian.com/platform/forge/runtime-reference/external-fetch-api/

@rmassaioli I have a similar need to read URL params within a Forge app but in Jira. It’s a blocker to moving across from connect.

See How to get the URL of a Forge app in Jira? - #7 by RhysDiab