Hi, Windows 10 has built in Black mode and also has a screen dimmer in build 1709 Fall Creators Update.

• https://blogs.windows.com/windowsexperience/2016/08/08/windows-10-tip-personalize-your-pc-by-enabling-the-dark-theme/
• https://support.microsoft.com/en-ca/help/4026946/windows-10-change-screen-brightness

Also can use https://justgetflux.com/ There is this, please read the Features :

• https://addons.mozilla.org/en-US/firefox/addon/new-tab-override/

Also can customize further with usserChrome :

• https://www.howtogeek.com/334716/how-to-customize-firefoxs-user-interface-with-userchrome.css/
• https://www.userchrome.org/
• https://www.accessfirefox.org/Firefox_Accessibility_Themes.php

Please let us know if this solved your issue or if need further assistance.

I reviewed your links. Thank you for them.

Without going into a lot of details I have tried these in years past. Each had pitfalls, complexity, or operational obstacles of one sort or another.

The now incompatible Screen Dimmer with its keyboard shortcuts and the magnification shortcuts served virtually all my browser viewing needs. Lightweight and a simple to use it was. One could not ask for better functionality.

Once I looked at rolling back to the previous FF version just to get Screen Dimmer back. It looked like another series of nightmares and headaches. My vision and life now take me away from such.

Is there some reason it cannot be updated to the current version? Just curious.

Thanks again for your thoughts,

I will remain hopeful someone one day soon will update Screen Dimmer.

mikeincousa said

The now incompatible Screen Dimmer with its keyboard shortcuts and the magnification shortcuts served virtually all my browser viewing needs. Lightweight and a simple to use it was. One could not ask for better functionality. Is there some reason it cannot be updated to the current version? Just curious. Thanks again for your thoughts, I will remain hopeful someone one day soon will update Screen Dimmer.

Updating that add-on would be up the people who originally created it, or by someone else depending upon the licensing it was created under. Plus it might require a complete rewrite rather than an "update" as was done for the 2nd version of Nov. 10, 2013 .

My guess is that it's just not possible to rewrite due to removed API's that just may not be available any longer.

Too bad.

What are the options for rolling back the current version?

Is there someway I could put this in front of the developers?

I did not see it earlier. I am going to try this next. https://www.pangobright.com/download.htm

Any suggestions along this line for Linux>

Did you try "Adjust Screen Brightness"? It has a very simple operation, but it doesn't include the bells and whistles like creating a rectangle that has normal brightness.

https://addons.mozilla.org/firefox/addon/adjust-screen-brightness/

First screenshot shows the slide control.

Second screenshot -- for CSS nerds -- shows the way this extension works: it injects a new element into the page using a custom style rule.

Unfortunately, the overlay doesn't appear only on the screen, it also darkens printouts. That definitely needs to be fixed; I couldn't use it myself unless that is fixed. (Edit: I submitted a request to the author for this.)

It also doesn't seem to be able to save per-site brightness preferences. Another possible improvement for the future if the author is open to it.

You might find info here : https://www.accessfirefox.org/ or you may want to contact a community help group that specializes with vision impairments.

There used to be before all this stuff came out in software a thing you hung over your monitor. Was sort of a screen and dimmed things.

No idea where you are.

I wander, sorry. Ya, as someone that used to work for a local Community Service as well as Prov Gov here in Canada I know if you phoned they would/should try to help or put you in contact with someone that could help find the software you need. G' luck in your search.

Thanks for the additional resource and thoughts. i will check them out. FYI the Pangolin dimmer https://www.pangobright.com/download.htm is working very well in Windows 10, almost like the old Screen Dimmer. But it lacks the shortcuts. On the upside it works across the file tree too, which the FF tool did not. That is a BIG plus.

In closing the essence of the problems with apps like those in W10 or FF is that they are mol fixed. They do not address the fact that there is a wide dynamic variance in brightness from page to page, the worst being a pdf of an old Currier mechanically typed doc on white paper of the day. Night and day demand different brightness setting too. Typically using the pango app I run between 30 and 80% brightness level going through that range several time a day /night.

Problem is that it takes three clicks to change a setting. I plan to contact the developers and see if they can hop it up.

I have been using Midnight Lizard more, and finding it helpful but still have to revert at times. I recall looking at some tweaks for it but found them complicated.

I will send a screen print of whatever I am looking at next time I need to revert. Maybe you will have quick fix?

Thanks for all you support and effort.

BTW I live in a small town in the high mountains of Central Colorado. Resources her can be as thin as the mountain air.

I think doing this well is a hard problem. Let's say an add-on author finds functions to:

• determine the "average" color of the viewport (the part of the document currently showing on the screen)*
• determine the perceived brightness of that color*
• adjust the filter to allow more of the display through for lower brightness and less of the display for higher brightness pages

The add-on still has some challenges:

• The average of large empty side areas you don't care about and the text/image areas you do care about may give a poor result. How can you handle those areas differently in an efficient manner?**
• When you scroll, the layout or content of the next area may be different enough that the previous calculation is no longer optimal. But constantly recalculating this is going to bog down the browser since there may be nearly 2 million pixels in the viewport.

Hmm... it's fun to think about. We need an intern. ;-)

* Some pages I looked at to see how complicated this might be: http://www.nbdtech.com/Blog/archive/2008/04/27/Calculating-the-Perceived-Brightness-of-a-Color.aspx , https://stackoverflow.com/questions/2541481/get-average-color-of-image-via-javascript , https://github.com/lokesh/color-thief , https://gist.github.com/olvado/1048628

** A linear-gradient background-image could give heavier shading on the sides than in the center, but how would you quickly figure out the boundaries of the respective areas with reasonable accuracy in a reasonable amount of time?