Has anyone used fast-components?
It’s from Microsoft and seems to be the base for a number of styled component libraries to build off of.
It also has really good support for Blazor, which if I remember correctly, is a sort of spiritual equivalent to liveview in the .NET works.
In essence, I guess if not directly support for them, maybe just some documentation around them? “Here’s a very popular web component or an example and here is how we would support it and some of the drawbacks you might encounter if you try and also do this with some random web component”.
Of course, if the answer is “sounds great! PR’s welcome” that’s perfectly acceptable 
I know morphdom and Shadow DOM based libraries are always going to be at odds unless accounted for, but I’d really love to see a mechanism or anointed path or something for how best to integrate them. I know that has been my hardest selling point to management that thinks JavaScript should enter our backend stack again, which I’ve been trying to avoid like the plague for a while, and am in the process of losing
