Nedas Petravičius spotted a new YouTube experiment that changes the user interface: there's a bigger sidebar that's now overlaid, the Dashboard/Video Manager/Analytics menu has been moved to the right corner of the page and the Upload button is blue. YouTube now shows the same sidebar from the homepage on video pages, so you no longer see a list of suggested videos.

The biggest change is that the video page is now centered. YouTube's pages used to be centered, but they're now aligned to the left, ever since YouTube redesigned the pages and added the sidebar guide. There are many extensions and scripts that center the pages. The new sidebar has a lot in common with the Google+ sidebar. There are some differences: you need to click the menu icon to display/hide the sidebar and the sidebar continues to be displayed when you click one of its options. Since the sidebar is hidden by default, there's more room for your favorite videos: This drop-down menu is placed next to the upload button in the regular interface: Here's a video:

Here's how you can enable the experimental feature. If you use Chrome, Firefox, Opera, Safari or Internet Explorer 8+:

1. open youtube.com in a new tab

2. load your browser's developer console:

* Chrome/Opera 15 - press Ctrl+Shift+J for Windows/Linux/ChromeOS or Command-Option-J for Mac

* Safari - check this article

3. paste the following code which changes a YouTube cookie:

document.cookie="VISITOR_INFO1_LIVE=ULHzU8CeVLo; path=/; domain=.youtube.com";window.location.reload();

4. press Enter and close the console.
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