What if the users browser has JS turned on but not support webworker / wasm?

[ForestJohnson]

in that case currently it looks broken. I fixed this for capsul by moving the part that draws the captcha into the progress update handler. that way it only draws if the webworker/wasm is functioning. Also, the readme and example should not disable the submit button in that case. Just handle submit without PoW in some other way on the server side.

See the capsul repo for an example of this:
https://git.cyberia.club/cyberia/capsul-flask/src/branch/main/capsulflask/auth.py#L105-L106

           if (not known_user) and (not valid_solution):
                return redirect(url_for("auth.email_request", untrusted_input_email=email))

https://git.cyberia.club/cyberia/capsul-flask/src/branch/main/capsulflask/auth.py#L173-L188

@bp.route("/email_request/<string:untrusted_input_email>", methods=("GET", ))
def email_request(untrusted_input_email: str):
    match_special_characters = re.compile(r"[^a-zA-Z0-9@+._-]+")
    sanitized_email = match_special_characters.sub("", untrusted_input_email)
    return render_template("email_request.html", redirect_url=url_for("auth.i_will_await_your_correspondence", untrusted_input_email=sanitized_email))

@bp.route("/i_will_await_your_correspondence/<string:untrusted_input_email>", methods=("GET", ))
def i_will_await_your_correspondence(untrusted_input_email: str):
    match_special_characters = re.compile(r"[^a-zA-Z0-9@+._-]+")
    sanitized_email = match_special_characters.sub("", untrusted_input_email)
    if wait_for_delivery_manager_to_recieve_email_from_user(sanitized_email):
        get_model().record_known_user(sanitized_email)
        return handle_login_post(sanitized_email, "", "")
    else:
        return redirect(url_for("landing.support"))

https://git.cyberia.club/cyberia/capsul-flask/src/branch/main/capsulflask/templates/email_request.html#L10-L20

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