Good

Much faster than other dark mode extensions, however it has a tendency to break icons and images.

loading fast than Dark Reader and work fine, good job
but sometime load "discard tabs" will break the web page

edit: After 2 year ago now I change rating to 4 star,
because even now it still easy to break the web,
When FF startup load "discard tabs" will not effect dark mode,
and whitelist sometimes not working(ex : reddit in wihtelist but this addon still blocking img)

Worked!

worked!!!

Truely fastest dark mode!. But I give 4 stars because dark mode is sometime not applied in case: back to previous page, some websites

Thank you for your work. Very promising, and an interesting underlying idea. Looking forward to see continued development!

Really nice and pratical add-on ! Even more so since last update patching reported website breakings.
My eyes can now keep gazing at the abyss.

if it handles accented letters and vharacters it'll get thwe 5 star! well done mate. Would be the best if those are okay. :) keep up!

THANK YOU! For creating this. I know that Dark Mode is purely aesthetic for some people, however because I am light sensitive. This is a freekin life-saver. Don't even care that I might have to whitelist some pages to keep them from breaking... This is worth it.

UltimaDark has the potential to be the best dark-theme add-on (ever). I'm using the word "potential" just because now UltimaDark is in "experimental stage". But the Dev is very active and responsive, and he is working very hard to improve the add-on, and to add new features. Progress can be followed at Dev' GitHub.

Yesterday the ON/OFF was included (among other improvements). And white-listing is already on the way. Other features are planned, and surely with time we're going to see great new stuff.

Most of the webpages work great with this add-on. And only few webpages have issues (but currently the Dev is working on it, trying to fix everything). It's worth mentioning that is impossible to build the perfect dark-theme add-on. Lot of webpages are badly programmed, and it's not easy to deal with them. Every dark-theme add-on has imperfections.

IMHO UltimaDark is great firstly because its browser performance (webpages have a good loading speed). And secondly, this add-on has very nice aesthetic results. In brief, this add-on is great for the relation: "Browser Performance" VS "Aesthetic results".

Thank you and congratulations to the Dev!

It seems to work well, with good performance overall, but it indeed breaks some websites. That why it needs a exceptions list feature (if possible with smart segments of url, like: whitelisting .example.com' , 'example.com/subcategorypages' or "subdomainonly.example.com' ), and maybe for later, alternative methods to darken the pages (simple inverse filter, CSS) if the main one doesn't work as expected.
Also, it'd be cool to let the browser highlight with a different color visited links.

Encouragement to the dev!