You are waiting for a live update (like sports scores or a sale). The "Aw, Snap!" error message appears.
Are you having trouble with a not updating, or is the physical key itself not responding?
To recap:
Occasionally, users find that pressing the top-row keys triggers different actions than the icons suggest. For example, if you press the Refresh key and your computer seems to be searching for something or adjusting volume, you might have toggled the "Treat top-row keys as function keys" setting.
If you are using your Chromebook in or prefer using the touchpad/mouse: Look at the top-left corner of the Chrome browser window.