Reader view is such an invaluable feature for me.

The icon sometimes doesn't appear in the address bar though (apparently because Firefox is unable to identify where the text content is in the page.)

I've also found the extension - Open in Reader View [1] to be useful for those situations.

[1] http://firefox.add0n.com/reader-view.html - Firefox, Chrome and Opera

High Contrast is another option for chrome that changes only the text and/or background colors.

https://chrome.google.com/webstore/detail/high-contrast/djcf...