Ionic 3.1 - white screen / missing 'main.js.map' on run

Hi,

Upgraded the app from 2 to 3.1 (following instructions). The app whitescreens on a --dev or --prod device or simulator run on iOS and Android. I do get the splash screen before the whitescreen, however the only console debug info I get is:

file:///Users/me/dev/netapp/www/build/main.js.map 
Failed to load resource: The requested URL was not found on this server.

Any idea what may be happening, or how I could squeeze out a bit more debug info to trace the issue?

Thanks,

Clint

Solved: the app.module.ts update had not been not carried out. Once IonicStorageModule was added, the app loaded.

ETA: the message about the missing ‘main.js.map’ remains…