Page DarkPage Dark
Available for Chrome too.
Functionality
Page Dark covers the webpage with a black screen when you click the toolbar button. Everything except media like videos or games, frames and Flash objects will be hidden by it. This allows you to watch online videos, play Flash games, etc in a much more enjoyable way.
Usage Notes
Implements Stefanvd's TOtL API, a mechanism created in 2010 to help websites interface with add-ons like TOtL (Mini) and Page Dark.
Please rate/review/support! :)
Problem/bug?
Do report it correctly and with enough information, using the provided support site/email links, so it can be properly discussed, investigated, and resolved.
Do not abuse reviews for groundless whining - it's against AMO rules, and for good reasons. If you intend to post a bad rating, you must put in some effort to back it up and communicate with me properly first. Many bad reviews that don't go through the support channels turn out to be unjustified (often PEBKAC), which is unfair and wrongly makes me look bad. Uninformative, uncooperative, and plainly incorrect negative reviews will be reported to moderators for removal. I don't have to tolerate lies and misinformation any more than you have to tolerate genuinely bad addons.