I will base my answer on the answer provided by Stefan Dobrev, as I am not sure if you ask about the camera confirmation screen or the support of custom plugins.
1) Adding custom plugins to your AppBuilder project is now possible. How to achieve this is explained in our documentation
2) The camera confirmation screen still cannot be modified. This remains the default behavior of the Cordova Camera plugin. I looked for a different plugin that offers this feature, unfortunately, I did not find any. With this in mind, the only way to create this functionality is by extending the Cordova Camera plugin or by implementing your own Cordova plugin. Both approaches would require extensive knowledge in native mobile development.
Having said that, currently, we do not plan to create custom implementation of the Core or Verified plugins.
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