Describe the bug
When being notified of multiple events, "Prev" and "Pause" have the same hotkey, and "Pause" is not accessible with the keyboard.

To Reproduce
Steps to reproduce the behavior:

1. Trigger multiple events at the same time (i.e. build/fill two warehouses at the same time)
2. Try to close the notification by pressing P (to pause)
3. Can't, because P is bound to the first button on-screen, which is the "Prev" button

Expected behavior
Somehow resolve the hotkey, I have no idea how it would be easiest.

• Rename the buttons ("Before" and "After" instead of "Prev" and "Next")
• Use the second letter of some word instead of the first, for the hotkey
• Disable/hide the "prev" button when on the first page (to let the user hit Pause)

Screenshots

Desktop (please complete the following information):

• OS: Linux debian 5.3.0-3-amd64
• Python version Python 3.7.5 (default, Oct 27 2019, 15:43:29) [GCC 9.2.1 20191022]
• Version Singularity 1.0a1 (commit: singularity-1.0a1-53-g6ce8ee2)