Thank you for your 4 stars review. And using the Turn Off the Lights Firefox extension!
In the Turn Off the Lights Welcome Guide I explain this feature. There are many ways to set the dark layer to 100% black. You can do that in the Turn Off the Lights Options page; Or in the double-click on the gray lamp button, that will open the mini settings panel. See this YouTube video tutorial: www.youtube.com/watch?v=nsmGfOAgcoE
Please do not use the review page as a support forum. I am happy to help you at www.turnoffthelights.com/support
