Added all URLs starting with "about:" in the exception list.

Credit to https://github.com/Youareyou64.
Details: https://github.com/chronakis/firefox-sticky-window-containers/pull/13

This is a maintenance release that fixes the issue about not being able to open preference, logins and other Firefox pages when the first tab is not the default container. Please see more details at the github page, https://github.com/chronakis/firefox-sticky-window-containers.

This is a maintenance release, the first after a year, that fixes the two issues below:

1. Issue #1 - Infinite loop when the first tab in the window is inside the facebook container. If the first tab is acebook, the extension will use the default container.

2. Issue #5 - New tabs close immediately when the "New tab" option is set to "Blank page". Fix provided by Douwe Maan <https://github.com/DouweM>.

Fixed opening the customize firefox page when in a non default container window.