I couldn't find dark mode on emacs. Help!

*buzzes in first* "What is modus-operandi theme?" I'll take "support requests in the form of a statement" for $0.00, Alex.

Emacs doesn't have dark modes, per say. What it has instead is color themes. There should be a bunch of bundled themes available if you look around in the menus. But there are also a many themes available on Melpa that can be installed through the emacs package manager. Try M-x package-list-packages and then use C-s "theme" no quotes -- to search by string.

Change your gtk-theme to a dark one.

That was surprisingly easy!! But I wonder why there Isn't a toggle for a dark/light mode🤦 Thanks!

Because Emacs predates this dark/light mode fad literally by decades. And nobody really needs it because you can achieve the same by configuring the desktop environment theme (that's what gtk-theme is) instead of doing it application-by-application. It is just a bit more painful in non-Linux environments because Windows and Mac users aren't likely to use GTK as their widget toolkit. So the theme isn't managed automatically when the rest of the environment is switched. Besides, light text on dark background is terrible from an ergonomics point of view (as are the various low contrast setups). There are plenty of studies on that - it causes much more fatigue than working in a well lit room and having dark text on light background instead.

> light text on dark background is terrible from an ergonomics point of view (as are the various low contrast setups). There are plenty of studies on that Not doubting you, but I'm interested in some sources on this. I've always preferred high contrast dark themes like modus-vivendi. I'm with you on low-contrast dark themes, which I've never found appealing. But this is the first time I've heard that dark themes in general could be a problem.

For example: https://pubmed.ncbi.nlm.nih.gov/23654206/ Or: Bauer, D., & Cavonius, C., R. (1980). Improving the legibility of visual display units through contrast reversal. In E. Grandjean, Vigliani (Eds.), Ergonomic Aspects of Visual Display Terminals (pp. 137-142). London: Taylor & Francis Also this overview has a lot of links: https://www.nngroup.com/articles/dark-mode/ And no, that myopia from long term exposure to "light mode" is not something you should be worried about - tiny cohort (7 people), not checking for possible confounders (such as whether exposure to *any* long time screen time could change your predisposition to myopia (there is likely a reason why almost all programmers wear glasses) and also they didn't actually measure whether or not the subjects became myopic. Only measured some changes in the eye which could (but doesn't have to!) cause it long term. The "dark mode" thing is mostly a design fad, the same as the "flat" interfaces that are so associated with "modern" look - and which are so terrible from the usability point of view. Old dumb terminals were all "dark mode" - bright text on dark background. Yet we have moved away from that the moment graphics became possible because for reading and manipulating text it was advantageous. If I can hazard a guess, I think the "dark mode" thing became so popular among developers and technical people in general because we tend to spend a lot of time in darkened/poorly lit rooms (less glare on screens, etc.), working late, etc. And there a bright white screen background can become quickly irritating and fatiguing. But the solution is to turn the light on and not use a stupid glossy screen, not to switch to "dark mode". Your eyes will thank you.

Nokia made "light mode" dumb terminals, which had high refresh ratio combined to slow phosphorous. They were great, like black ink on white paper.

Yes and on most dumb terminals you could invert the video and have dark text on bright background too. But few have used that, the small CRTs of these things didn't look all that great in that regime.

Isn't modus-vivendi the dark one?

Yeah lol

Hi - thanks for the references! Several decades ago, I used to think there must be "one answer" to the question of dark vs. light mode. I haven't given it much thought in many years, and I've spent plenty of time using both setups. I was interested in your claims regarding light vs. dark mode, and definitely appreciate the references. My instinct these days - based on years spent in science as well as my own past tendency for overly "prescriptive" thinking (and particularly trying to find "hard metrics" such as spherical aberration / appeal to fundamentals like optical principles in general) - is to doubt very specific claims about "best in general" when it comes to something like ergonomics. And, I mean this beyond merely the basic caveat that there are always exceptions. In particular, and I'm curious if you have references that address this: I pulled up the reference [Positive display polarity is advantageous for both younger and older adults - PubMed stub](https://pubmed.ncbi.nlm.nih.gov/23654206/) (I skimmed the actual article, not just what's on PubMed) and as far as I can tell, it does not appear that the authors addressed a couple of potential confounding factors. Specifically: 1) the fact that many people may be far more used to carrying out the *reading* task (or even anything involving a letter-like shape) in "positive polarity", and 2) the authors do not seem to have adjusted the background lighting in their tests - i.e., they used the same ambient lighting across all tests of light vs. dark mode. If I'm mistaken on either point, I welcome correction in terms of this specific article as well. In any case, in my experience, I find the biggest issue seems to be transitions / overall contrast. That is, if I spend a lot of time in a relatively dark room, everything on my screen is negative polarity, etc, this works well. And, to be honest, I find myself personally less visually fatigued overall (n=1 of course). However, if I'm in an environment where I'm dealing with brighter light, positive polarity (e.g. having to consult text on paper), etc., then it's better to keep everything positive polarity. Do you have some additional information / thoughts regarding these factors / my concerns regarding that paper? I greatly appreciate any feedback and any chance to learn something new! Thanks!

I think you would need to do your own research on this, I am certainly not an expert on neither human perception nor on human physiology, only learned enough about these issues when dealing with general usability questions. AFAIK, the "being used to something" may be a factor - but given that pretty much everyone learns to read and write in school on paper these days, it would be rather difficult to control against. However, those papers were measuring things like perceived fatigue - that goes beyond just "being used to" something (that would impose a mental strain but not physical eye fatigue), for example. Concerning contrast - yes, that's definitely a factor. Too high contrast (especially in negative polarity) tends to cause eye strain and fatigue, too low contrast hurts legibility of text and causes mental fatigue. Also keep in mind that most of these studies were concerned with typical office workers - who need to consult paperwork, deal with colleagues,etc. - dark rooms are not conducive to that. If you are a typical programmer that is "sunlight-shy" and works in a dark room with no/little reference to paper these days, then bright text on dark background could be still more comfortable, even though not more legible. So these recommendations may or may not be applicable, depending on what exactly is the nature of the task the person in front of the screen is performing.

Very fair. Good point about the 'typical office workers' in particular. I would imagine that does constitute the vast majority of users and 'user-hours'. So, whether or not the authors of that specific paper were intending to imply a stronger conclusion in general than is warranted IMO, their conclusions should arguably still lead to more optimal design choices across the entire population. Thanks for some useful information and discussion to consider! PS - I'll have you know I'm hardly 'shy' when it comes to the sun: why, I used the 'solarized' color scheme just the other day! 😄