app_key for Dropbox is null

Problem/Motivation

After configuring Dropbox with the correct App Key, file Chooser does not work because app_key in the url is null. If you copy the URL to another window and replace "null" with the correct Api Key, the Chooser file works fine.

Steps to reproduce

On a fresh installation of Drupal 10.1.7, install the External Media module 1.0.22, configure Dropbox, modify Article´s Image form display, and create a new Article. When you press the Dropbox buttom, a popup appears with the error "Invalid app_key". If you copy the URL into a new window, and replace "null" with the correct Api Key, the Chooser file works fine.

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes