Topic: How to extend the image plugin?

I want to extend the built-in image plugin in TinyMCE but I couldn't find a way to do it.
For example I just want to add additional field in the popup and then apply its value to the image, I also want to hide/disable the "Styles" input field. And that's all.
I don't want to re-invent the wheel and write my own plugin that will mostly copy-paste the existing code, I want to know how I could extend the existing plugin.
I've checked the documentation, the Wiki and searched through the TinyMCE forum and StackOverflow. At last I even started exploring plugin's source in GitHub but still can't find a solution...

Thanks in advice!


Re: How to extend the image plugin?

I've been looking for a similar thing so I can add back the image preview functionality of version 3.