On the visual side this add-on works very well. BUT it seems to have a SECURITY ISSUE, since when it is activated certain website logins (e.g. a bank) don't work anymore. I wonder how this is possible since the add-on supposedly only alters a websites colours.

I do not understand how this can be a recommended add-on. Yes, it does the job and it looks pretty and all that. But I have never had an add-on that made my pages freeze up and cause my browser to crash before this. It's almost impressive to see how they managed to mess up such a simple thing. Refreshing pages take forever and when I resize my windows all of my tabs lock up, stuck between the original width, to the new width and everything in-between. How do you manage to make something that is supposed to only change the appearance but somehow invents more problems??

Didn't appear on tool bar or tool-bar drop down. Didn't have any kind of settings like those show on website help page. Didn't do a darn. Bye-bye.

No longer works at all. Completely useless.

Sending crap back to their servers.

CAN NOT RECOMMEND! Significantly slows firefox for Android down!

this add-ons completely broken after Version 4.9.39, you can still download old one in release page of github if you want.

I have no idea how this is a recommended addon. When adding it to Firefox, a tab opens up with what appears to be a book they are selling, unrelated to this addon. I reported this, and I would advise you to steer clear.

Breaks mobile browser

rubbish

As well as it works for the chrome bois (chrome, edge, brave), on firefox it is a whole other story. it makes my videos and scroll grind almost to a halt, it is extremely laggy.
What's more, it modifies colors within photos and youtube - it desaturates the youtube video for example - its so frustrating that i prefer burning my retina on random light modes at this point.