[Zababa]

> Such a waste of resources (but it's not your resources, so developers don't care).

I've always wondered if it wasn't intentional. Things running on the client means they don't have to run on the server, and you can save money this way.

[kevincox]

For things like syntax highlighting which is fairly cheap and done "once" I doubt resource usage is a consideration. However I won't be surprised if this is at least a consideration for bigger companies when they decide to make a relatively cheep API or a server-rendered app.