Hello,

I have an issue with the 'url-retrieve' function:
If the target url returns a redirect, the 'Authorization' header is not
sent on the redirect url.

Example:

List of endpoint:

http://localhost/a: 308 redirect to http://localhost/b
http://localhost/b: display all received headers

I will be using 'url-retrieve' on url 'http://localhost/a' with headers:

Authorization: Basic YWxhZGRpbjpvcGVuc2VzYW1l
X-ExampleHeader: foo

The response shows 'X-ExampleHeader' but not 'Authorization'.
Is there a way to forward 'Authorization' aswell?

Here is a code sample:

(let ((url-request-extra-headers '(("Authorization" . "Basic
YWxhZGRpbjpvcGVuc2VzYW1l")
                                   ("X-ExampleHeader" . "foo"))))
  (url-retrieve "http://localhost:5000/a" (lambda (status)
                                            (display-buffer
(current-buffer) t))))

Server in Python with flask (pip install flask):

from flask import Flask, redirect, request, jsonify

app = Flask(__name__)

@app.route('/a')
def a():
    return redirect("http://localhost:5000/b", code=308)

@app.route('/b')
def b():
    return jsonify(dict(request.headers))

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)

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