Built-in dark mode for web contents

[batata]

I love extensions like Dark Reader that automatically transform any website with a dark theme. The way they do this is by injecting many new styles into the DOM, it works but there is two main drawbacks to this method :
- there's a latency that makes contents blink
- it reduces performances on some websites by a lot

So It would be great if there could be a built-in low level solution (directly in web render?) that would swap colors on the fly without editing the page styles and thus would solve the two aforementioned issues.

[sus_scrofa]

I would also love to see the idea finally implemented. In the meantime, I'm using Ultima Dark, an open-source addon that is agressively enough and avoids white flickering: https://addons.mozilla.org/en-US/firefox/addon/ultimadark/

(I'm not affiliated in any way with the development of the addon, just a user of it.)

It would be a dream to have this feature implemented di into firefox, since the source code already exists, so I could not just decide if I want a website to use enhanced tracking protection, my webcam, microphone etc. but also if I want a website to be darkened or not (e.g. because it already has a great dark mode)

[SphinxMan]

Seems like this has been kicking around for a few years now. I really want to like Firefox, but having an (albeit open source) extension be able to read every site I log in to doesn't sit well with me. I tend to use Brave if I have to do anything banking or medical related and Firefox for more casual stuff.

The trouble is, once I have Brave open in the evening, then I just carry on using it and it works beautifully, so there's no impetus to return to Firefox. I mostly use Firefox at work now, because I work during the day and this missing feature doesn't bother me when the sun's up!

[Puskara]

Make Dark Mode the browser default or request both light and dark by default

Many folks seem to prefer dark-mode.  IME the prevalence of light-mode is purely because it is the default.  Many users would prefer to use dark-mode but won't as light-mode is the default and making this change exposes them to a higher risk of fingerprinting and thus a loss of privacy.

My proposal is to make dark-mode the default for all Mozilla browsers.  This will mean that everyone will get to enjoy the benefits of dark-mode while not compromising privacy.  Alternatively, Mozilla could change the browser to always request both light & dark data and hide what the user is actually seeing behind a layer of abstraction which would always give a standardized response to what mode is being used.  This would preserve everyone's privacy and would allow everyone to select light or dark mode as they saw fit.

[Jon]

(Note: similar ideas have been merged into this thread)