I am going to use less.js and I doubt about Internet Explorer 9+. At LESS site they write following:
LESS runs on both the client-side (Chrome, Safari, Firefox) and server-side…
But there isn’t IE in the list. I just want to know does anybody use less.js and there aren’t problems with IE 9+?
Cannot speak about the client side, but i can recommend to use it on server side.
There are tools like SimpleLess which can generate the css files at design time, so you can place the finished css files on your server. That way you never have to worry about browser support and JavaScript, and your server has not more work to do. As a bonus you can automatically get minified css files, and you can assemble several css files into a single file.
For my sites i cannot think about writing the css files without
lessanymore.