A native sidebar system

I’ve noticed there’s a lot of demand for sidebars.

Just take a look at Search results for 'category:feature sidebar' - Discourse Meta

We’ve already got a lot of plugin and Theme Component choices, but now we’ve deleted the Category column, wouldn’t it be nice if this was native and provided plugin outlets in the native sidebar(s), so adding widgets would be super easy?

There’s currently a lot of ‘reinventing the wheel’ going on


That is a good idea, but I am more interested in header and footer choices being a part of setup wizard in 2.3 cc @Johani