When you hover your mouse over a reservation, the details show up in a pop up message.
Like this, you can quickly check all your reservations, without having to open all of them.
If the pop up message does not appear, it is blocked by the TeamViewer share plugin.
The issue can easily be solved by disabling the TeamViewer share plugin.
1. Click on the 'double arrows' on top of the screen.
2. Click on 'Disable this feature' at the bottom of the dropdown menu