Ionic3 iOS Icons are missing on app resume clicking on push notification

In ionic3 iOS, when opening app able to see all icons and images from assets folder. When app is in background and clicking on push notification, app opens but all icons and images from assets folder goes missing.

In below image all the squares or rectangles you can see are missing icons and images after opening app using push notification.

This issue occurs only in iOS. how to fix it?

One more input regarding navigation structure.
I have developed own scrolling tabs alike component, clicking on any tab icon, it sets the relevant page as root page. So probably on resume, the root path can be vary.