Sure it can. They can just say something like "IE9+ is supported, but features x and y won't work". There are plenty of libraries that officially support IE, e

Sure it can. They can just say something like "IE9+ is supported, but features x and y won't work". There are plenty of libraries that officially support IE, even when there are problems in a few small cases. They usually just make sure these issues are publicized so people won't be surprised them.