Fade-in-not-out animation flashes on ios

I’m using fade-in-not-out animation on tabs, it works well on android (cordova and chrome) and on pc (chrome), on ios 7 (iphone 4s) the animation flashes every time I enter a tab.

Tried both inside cordova and directly on browser, the bug is consistent.

I forked the sample “Tabs and Navigation”: http://codepen.io/dusty73/pen/unwpa

I tried it with ionic beta4 and beta5