Account verification not reactive across windows

[th0rgall]

Since the fixes mentioned here #98 (comment), the following scenario works:

1. Create an account in tab A in window W
2. Open a verification link via email in tab B in window W
3. Both tab A & B will have been notified of a fully verified account.

However, these updates don't seem to propagate across windows:

1. Create an account in tab A in window W (e.g. on your mobile phone)
2. Open a verification link via email in tab B in window D (e.g. on your desktop)
3. The account Tab A will be unverified until you reload the page.

There are also different scenarios possible for how Tab B looks when opened in a different context from tab A. See #298.