I tried to embed a disqus forum in my Chrome extension but they prevent embedding from a different domain (none in this case, as its an extension) than the forum is registered with. Does disourse allow such embedding?
No, Discourse does not support embedding in this manner.
Thanks Jeff. Hmmm is this limitation easy to remove in my own branch of the software?
Why not simply embed the RSS via a RSS reader, or write a quick set of API calls that return the necessary topics.
Because your code is a chrome extension, that means it can ignore cross-origin restrictions, and this is a trivial task to perform. Just request /top.json.