Many I've tried, but this takes the top spot for me.

wow amazing works fantastic I can change colors Thanks for this beautiful Add-On Web Extension....

Sorry to report here, but the reporting form on your fails to submit every time I hit 'Send' and just says Contact Admin.

When DM is active on flickr pic pages, the pic does not appear, but does when DM is switched off.

I've also noticed the header background image disappears on some web sites when DM is active.

Not a great problem as you have been clever enough to place the on/off switch on the toolbar for quick access.

FF 55: the checkboxes for theme selection are not visible

Nice theme, thank you!

I really like this app. One more thing would make it perfect : change the Firefox "browser theme" to a designated dark theme when a dark "page theme" is activated.

That would be great for the eyes.

Thanks for your work!

Love the custom style for all commonly-used pages.

Good! Thank you!

Unfortunately also the videos became darker with all styles.

EDIT: New version 0.1.2 and style n.5 fix the video problem.
Thanks.