These 2 pages (and some others) display okay (black text on a white background) for me in Firefox ESR (v52), whereas they are very hard to read (light gray text on white background) in the latest Firefox (v57):
http://www.motherjones.com/crime-justice/2017/12/a-brief-blood-boiling-history-of-the-opioid-epidemic/
https://www.theatlantic.com/business/archive/2017/12/ride-hailing-new-york-traffic/549131/?single_page=true
What is causing the gray text? I restarted with add-ons disabled, and the text is still gray.
...Ok, so in my browser settings, the default text color was set to gray. The above pages must specify the background color as white, but must not specify a text color. (If you design a web page, you should either specify both colors or neither, not just one of them.) Those pages were using my default gray text color on their background white color (my default background color was dark, not white). Changing my default text color to black fixed the problem.
http://www.motherjones.com/crime-justice/2017/12/a-brief-blood-boiling-history-of-the-opioid-epidemic/
https://www.theatlantic.com/business/archive/2017/12/ride-hailing-new-york-traffic/549131/?single_page=true
What is causing the gray text? I restarted with add-ons disabled, and the text is still gray.
...Ok, so in my browser settings, the default text color was set to gray. The above pages must specify the background color as white, but must not specify a text color. (If you design a web page, you should either specify both colors or neither, not just one of them.) Those pages were using my default gray text color on their background white color (my default background color was dark, not white). Changing my default text color to black fixed the problem.