HTML5: Referencing one HTML page from another HTML page

I was trying to reference a HTML file B from an HTML file A, without using a server (“server” in this context as in Node or IIS), because I wanted something very lightweight. However, while HTML5 introduces the ability to do such referencing, when trying to do it via a File protocol, it constantly fails with errors stemming from (quite reasonably, I think) restrictions imposed by Cross-Origin Resource Sharing:

In the end, I gave up, and used Node and Express as a light-weight server. Diagram with the key points here – you can download it as SVG for the detail.

Credit due for the Node/Express example here, and for the pointers on HTML5 HTML links here.