Browser Window & Tabs:

Ctrl + Tab = Switch to Next Tab
Ctrl + Shift + tab = Switch to Prev Tab
Ctrl + Shift + W = Close browser window comprising of multiple tabs
Ctrl + Shift + T = Open recently closed tab

General Browser Features:

Ctrl + J = Download History
Ctrl + L = Search bar
Ctrl + H = History
Ctrl + S = Save Page as
Ctrl + A = Select all
Ctrl + R = Refresh Tab
Ctrl + W = Close Tab
Ctrl + N = New Browser Window
Ctrl + T = New Tab

Bookmarks

Ctrl + Shift + O = Open Bookmarks bar
Ctrl + D = Add Bookmark
Ctrl + Shift + D = Bookmark all open tabs at once

Dev Tools

Ctrl + Shift + I/J = Console Tab
Ctrl + Shift + C = Elements Tab
Ctrl + U = Page Source