https://support.mozilla.org/en-US/kb/keyboard-shortcuts-perform-firefox-tasks-quickly
ctrl-tab move one tab to right
ctrl-shift-tab move one tab to left
alt-# switch to tab # (1-9)
ctrl-l jump to URL field
See this support page.
- Click on little lock icon next to URL
- Then "Connection secure"
- Then "More information"
- Then the Permissions tab
- Revise "Send notifications" to "block"
- Revise "Open pop-up windows" to "block"