Differences between firefox and chrome when using flex-basis?

Question

css

Please tell me why the result in firefox and chrome is different.
https://jsfiddle.net/0sokqyhg/upd

. And yet, on mdn it is written

Attention: in case the element has flex-basis (other than auto) and width (or height in case of flex-direction: column) set at the same time, flex-basis takes precedence.

I set the width in the example above, and the result changes. https://jsfiddle.net/1xu74smj/ although how should it be ignored.