While this is completely true, RandoAwake only has permissions to display notifications.

Take another Extension like Tab Limiter that needs to read data in other contexts. It requires more permission and those permissions are displayed when you install it.

When making a Chrome extension you have to select permissions, and I selected the least amount I needed.

• Notifications to do Desktop Notifications
• Alarms to control the delay so we don't hammer Steem every five seconds.
• Storage so I can save preferences like Enable Desktop Notifications/Sound and the Delay.

There is no way I can get out of the sandbox without additional permissions, and when you do they will be listed. For example, another plugin called Facebook "AdBlocker" it has permission to read data on all sites, not only just Facebook.