Whilst is awesome to be able to use flexbox quite freely IE11 and Safari still have a handful of slightly arcane issues, such as certain configurations of flex-

Whilst is awesome to be able to use flexbox quite freely IE11 and Safari still have a handful of slightly arcane issues, such as certain configurations of flex-wrap:wrap content requiring max-width:100% or flex-basis:auto to trigger the wrap rather than overflowing. The golden rule of Flexbox layouts in those browsers seems to be "too much Flexbox breaks Flexbox"!