On the Unroll.Me website:
Viewing an email in your Rollup is easy! To view an email preview, simply click on it in the "Rollup" tab. For a full preview, double-click on the email.
On the Unroll.Me mobile app:
Viewing a full email in your Rollup is easy! Just tap on the email in the "Rollup" tab in your mobile app to see the full email.