Migrating from ionic 3 to ionic 4 doesn't look and feel as easy as the ionic team say.

1. How do i add extra custom icons compatible to tabs, buttons and everything

<ion-icon name="my-custom-icon"></ion-icon>
<ion-tab label="Music" icon="my-custom-icon"></ion-tab>

Without a documentation or tutorial, migrating would be a waste of my time. Alot has changed and thus far, this seems to be the most painful