3D transform functions should be stripped for IE9

Per Can I Use, IE9 supports transforms with the -ms prefix, but not 3D transforms. IE10 supports 3D transforms, but does not use the prefix. Can a “hack” be added to strip all 3D functions (*Z() and *3d()) for the -ms prefixed rule?

Input:

transform:translateX(10px) translateZ(0);

Output:

-webkit-transform:translateX(10px) translateZ(0);
-ms-transform:translateX(10px) translateZ(0); /* invalid and ignored in IE9 */
transform:translateX(10px) translateZ(0);

Expected Output:

-webkit-transform:translateX(10px) translateZ(0);
-ms-transform:translateX(10px);
transform:translateX(10px) translateZ(0);

[ai]

@EasterPeanut

1. Update your Autoprefixer. The latest version in 7.1.2.
2. Check that you have IE 9 in your target browsers. For example, default browsers doesn’t contain IE 9 anymore. Try http://browserl.ist/

[EasterPeanut]

This is a great solution because translateZ will now be ignored in IE9. But when I try this as input (as fallback for IE9):

-ms-transform: translateX(10px);
transform: translateX(10px) translateZ(0);

I get this same output (-ms-transform property gets removed):

-webkit-transform: translateX(10px) translateZ(0);
transform: translateX(10px) translateZ(0);

When I try this in the autoprefixer playground, I do get the expected output though; including the -ms-transform. In my project (Webpack project) I am using autoprefixer 6.7.7. Any idea on what could be causing this?

Edit: never mind, already found out! It was the browser list in the package.json that had to be changed.