CUSTOM LOCALIZATION PLUGINS: Rich Text Block Widget

Despite lacking experience, I’m trying to make a custom “text and localization” plugin with inline images feature, starting with Rich Text Block palette.

So that instead of “<img id=” I want my “input” to be “<tid id=”. Plus be able to colour it with “<colortext="Red">Warning.</>"” and scale it with “scale="1.5"”. Unless something like that is already built into the engine (in that case, I want to be customized to my… input strings or something).

To make something like this in total: Press <tid id="AtkPrim"/> to <colortext="Red">attack</>."

Where should I start or access the Rich Text Block palette to create my own Rich Text Block palette for Widgets?