Steps to reproduce (*)

1. On a .less file, import the following URL: @import url("https://fonts.googleapis.com/icon?family=Material+Icons");
2. Compile LESS

Expected result (*)

• Font is imported correctly

Actual result (*)

• We get this error: File https://fonts.googleapis.com/icon not found

Root cause

We originally found this issue in Magento 2: magento/magento2#25119

We were able to track down the issue down to the less.php library. This URL doesn't work because it doesn't have the "css" word in it, which the library takes into account when importing css files: https://github.com/wikimedia/less.php/blob/master/lib/Less/Tree/Import.php#L44