To enable extended accelerators for the Bookmark bar
1. Choose File - Preferences - User Preferences.
2. Select Basics.
3. In the Additional Options box, select "Show extended accelerators."
To use extended accelerators in the Bookmark bar
Once you enable extended accelerators, press ALT+B to display them on the Bookmark bar.
You can use the accelerator keys as follows:
To use extended accelerators in window tabs
To use an accelerator, press ALT+W, followed by the number that appears next to the window tab.