Example: http://www.csstrashman.com/styles/38305

All values which webkit considers invalid (anything prefixed with another vendor's prefix) is discarded.

The following two rules of are examples of this:

display: -ms-flexbox;
-ms-flex: 1 1 auto

A possible solution (albeit messy and not that great in general) would be to run the resulting CSS through a prefixer.

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