Earlier quoted context omitted.
I agree with you that since your elements appear to not be a part of the HTML5 spec they must be custom and are directives, wouldn't it be a good idea to mark them as such in some way? Maybe prepend them with "an-" or something? The reason being, considering that HTML5 is an ever evolving spec that it might be possible for a new element to be introduced that could be using the same name as one of your examples. That…
Maybe prepend them with "an-" or something? Yes, this is actually the recommended practice from the documentation. Built-in Angular directives are typically prefixed with `ng-`, and they suggest that other projects/developers use their own prefixes to avoid conflict.
Why not use XHTML at that point? If XHTML ever had a clear mission statement in life it was that.
I mean I thought XHTML was a curse a few years ago when it was The Thing Every Good Designer Uses™ since it couldn't be rendered as XML in the most popular browser. But hopefully that's not as much an issue anymore. Or maybe it is. I haven't kept up with IE.