Panic Button 4.3 alpha 3

An alpha release of the next version of Panic Button, tentatively numbered 4.3. Requires Firefox Developer Edition to install.

This alpha release is made available for testing purposes only. It may be unstable and may contain serious bugs. Install and use at your own risk.

What's New:
• Changed default keyboard shortcut to F8 to avoid conflict with toggling Reader Mode on Windows 10 (issue #49)