This is what’s known as a destructuring assignment, and it’s a new feature of JavaScript 1.7 (and ECMAScript 6) (Currently, only available as part of the Firefox JavaScript engine.) Roughly, it would translate into this: var ActionButton = require(“sdk/ui/button/action”).ActionButton; It seems silly in this example, as there’s only one item being assigned. However, you’d be … Read more
A MIME type is a label used to identify a type of data. It is used so software can know how to handle the data. It serves the same purpose on the Internet that file extensions do on Microsoft Windows. So if a server says “This is text/html” the client can go “Ah, this is … Read more
AdBlockers usually have some rules, i.e. they match the URIs against some type of expression (sometimes they also match the DOM against expressions, not that this matters in this case). Having rules and expressions that just operate on a tiny bit of text (the URI) is prone to create some false-positives… Besides instructing your users … Read more