Firefox—my browser of choice—just updated to version 41 beta. It turns out that from this version on, any extension that hasn't been signed by Mozilla is disabled automatically. Firefox didn't warn me about that. I had to go to the Add-ons panel to check why some of my extensions were not working, only to find that they were disabled. And I can't seem to find a place in the UI to opt out and allow unsigned extensions in my browser.

For a long time, an easy way to get access to a Firefox OS phone was to order a Peak or Keon model from Geeksphone. The phone maker jumped on the Firefox OS train early on, offering reasonably priced phones aimed to early adopters.

I’ve been checking out Pyret, the new language from the same guys that made Racket. Even if it is designed to be for education, it has a syntax I love and some really cool features, like the possibility of adding in-line unit tests to your functions.

Code coverage is invaluable to get an overview of how well-tested your app is, and it helps finding new bugs in your code. Unfortunately coverage reports are not ubiquitous in Node.js projects, and because of that it may seem that it is hard to set up, which is not the case at all!

Let's say you need to show a scrolling list with millions of rows, or even a reasonably big list with visually complex rows, each one composed by several DOM elements or CSS3 effects. If you try to render this the naive way, for example by appending rows into a DOM container with the CSS overflow property set to scroll (or auto), you will most likely run into performance issues.