We're considering the best method to support the ever-growing number of attributes (html/css) both standard and browser-specific ones.
The fact that HTML5 has no DTD (which we use internally to validate the HTML we output) means we must either add all valid attributes to the codebase manually, or introduce a way for the modeler to bypass validation in certain cases.
Whatever solution we choose, I'm pretty sure it will not apply to the "old" Tersus/Display/* plugins, but only to the newer generic HTML Tag and Tersus/UI/* plugins.
We'll provide more information once we have it.
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