Internet Explorer grayscale not working

If there’s a solution to it, I haven’t pursued it, as it isn’t an important path to pursue for me. The only effective value to the grayscale control is to get a sense, as a designer or site owner, how your site’s design works in the absence of color – which is a tool to help identify whether it may pose problems for visitors with various color and contrast perception challenges.

It doesn’t serve any beneficial purpose for visitors to your site, and since the color perception of the site isn’t dependent on any specific browser as a general rule, there’s no specific benefit to being able to test this in IE, as long as you’re able to render the change in some browser.