Hello @Benjamin Heap ,
Welcome to the MS Q&A forum.
Thank you for your question. As I understand, your end goal to configure Azure AD B2C sign-in to provide authentication for a web application that is designed to work without JavaScript.
Unfortunately, the dependency upon JavaScript being enabled on the client side is a hard dependency.
B2C needs access to JavaScript to run some server side files, so it is not possible to run it without it enabled. The behavior is by design. Currently, there is no known alternative to this.
I found few similar feature requests "Offer single-sign on without javascript", "Use progressive enhancement to allow non-javascript browsers to access", etc, already raised in Uservoice on feedback forum. If interested, you may upvote it. In general, Azure feature or product team would check feasibility of a feature request, prioritize against existing feature backlog, add them in roadmap as appropriate and would announce and/or update the related Azure document once a feature request is addressed.
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