Undo close current browser tab

`Ctrl` + `Shift` + `T`

All hotkeys for Firefox (Windows)

Address Bar Jump to address bar	`Alt` + `D` / `Ctrl` + `L` / `F6`
Address Bar Complete a .com address in address bar: adds "http" prefix and ".com" suffix to entry, then loads the page. Add alt to combination to load page in background tab.	`Ctrl` + `Enter`
Address Bar Complete a .net address in address bar: adds "http" prefix and ".net" suffix to entry, then loads the page. Add alt to combination to load page in background tab.	`Shift` + `Enter`
Address Bar Complete a .org address in address bar: adds "http" prefix and ".org" suffix to entry, then loads the page. Add alt to combination to load page in background tab.	`Ctrl` + `Shift` + `Enter`
Address Bar Open URL history in address bar and navigate. Press enter to launch selected webpage	`Arrow Up` / `arrow down` in address bar
Address Bar Delete current entry from address bar history	`delete` in address bar history
Search Bar Jumps to search bar if installed (ctrl+e used to do so as well, but seems to be discontinued)	`Ctrl` + `K`
Search Bar Toggle search engines	`Alt` + `Arrow Up` / `arrow down` in search bar
Search Bar Choose from previous searches. Press enter to choose selected search term	`Arrow Down` / `arrow up` in search bar
Search Bar Delete previous search entry	`Delete` in previous searches
Navigation Jump to homepage	`Alt` + `Home`
Navigation One page backward / one page forward	`Alt` + `Arrow Left` / `Arrow Right`
Navigation Open new tab in same window	`Ctrl` + `T`
Navigation Jump to next browser tab	`Ctrl` + `Tab` / `Ctrl` + `Page Down`
Navigation Jump to previous browser tab	`Ctrl` + `Shift` + `Tab` / `Ctrl` + `Page Up`
Navigation Jump to browser tab 1 - 8	`Ctrl` + `1` ... `8`
Navigation Jump to the rightmost tab regardless on how many tabs are open	`Ctrl` + `9`
Navigation Close current browser tab	`Ctrl` + `W`
Navigation Undo close current browser tab	`Ctrl` + `Shift` + `T`
Inside Webpages Get "focus" on webpage for in-page keyboard navigation. Note the dotted frame around the page	`Alt` + `D` , then press `Tab` twice (or three times)
Inside Webpages Scroll webpages up or down one line	`Arrow Down` / `Arrow Up`
Inside Webpages Scroll webpages up or down one page. space/shift+space does the same.	`Page Down` / `Page Up`
Inside Webpages Jump to beginning / end of webpage	`Home` / `End`
Inside Webpages Jump to next / jump to previous link	`Tab` / `Shift` + `Tab`
Inside Webpages Open selected link in current tab	`Enter`
Inside Webpages Open selected link in new foreground tab	`Shift` + `Ctrl` + `Enter`
Inside Webpages Open selected link in new background tab	`Ctrl` + `Enter`
Inside Webpages Open selected link in new window	`Shift` + `Enter`
Inside Webpages Download selected link	`Alt` + `Enter`
Inside Webpages Increase or decrease text size	`Ctrl` + `[` + `]` / `Ctrl` + `-`
Inside Webpages Default text size	`Ctrl` + `0` (zero)
Inside Webpages Reload page	`F5` / `Ctrl` + `R`
Inside Webpages Reload page with cache override	`Ctrl` + `F5` / `Ctrl` + `R`
Inside Webpages Stop loading page	`Esc`
Inside Webpages Jump forwards / jump backwards between tab bar and page. To reach addressbar, press f6 until reaching the tab (see dotted line around tab) and press tab	`F6` / `Shift` + `F6`
Inside Webpages Open context menu of a hyperlink. Press arrow up or down or initial letter to select command	`Shift` + `F10`
Inside Webpages Turn caret mode on or off (navigation with keyboard)	`F7`
Inside Webpages Select all, useful to copy and paste text out of webpages	`Ctrl` + `A`
Inside Webpages Copy selected text	`Ctrl` + `C`
Inside Webpages Print	`Ctrl` + `P`
Inside Webpages Print preview	`Alt` + `f` , then `v`
Inside Webpages Show page source	`Ctrl` + `U`
Inside Webpages Save page as	`Ctrl` + `S`
Search Open "quick find" window and searches phrase as you type	`Ctrl` + `F` / `[` / `]`
Search Open "quick find" (links only) window	`'` (apostrophe)
Search Find next occurrence of search term.	`Ctrl` + `G` / `enter` or `f3`
Search Find previous occurrence of search term.	`Ctrl` + `Shift` + `G` / `Shift` + `F3`
Search Close search window	`Esc`
Bookmarks Show or hide bookmark sidebar	`Ctrl` + `B` / `Ctrl` + `I`
Bookmarks Organize bookmarks	`Ctrl` + `Shift` + `B`
Bookmarks Add bookmark	`Ctrl` + `D`
Bookmarks Bookmark all tabs. In the "create in" menu, use alt+down to choose bookmark destination	`Ctrl` + `Shift` + `D`
Bookmarks Open bookmark menu and press first letter of a bookmark name to load them. More than one entry with the same letter, requires to repeatedly pressing the letter and hit enter	`Alt` + `b` , then press `a` - `z` / number
Firefox Features Open or close download window	`Ctrl` + `J`
Firefox Features Show or hide browsing history	`Ctrl` + `H`
Firefox Features Clear private data (menu)	`Ctrl` + `Shift` + `Delete`
Firefox Features Open file	`Ctrl` + `O`
Firefox Features Open Location	`Ctrl` + `L`
Firefox Features Open file menu	`Alt` + `F`
Firefox Features Open edit menu	`Alt` + `E`
Firefox Features Open view menu	`Alt` + `V`
Firefox Features Open history menu	`Alt` + `S`
Firefox Features Open bookmark menu	`Alt` + `B`
Firefox Features Open tools menu	`Alt` + `T`
Firefox Features Open help menu	`Alt` + `H`
Firefox Features Show / hide Add-On Bar (holding add-ons)	`Ctrl` + `/`
Firefox Windows Opens new browser window	`Ctrl` + `N` / `Alt` + `F` + `N`
Firefox Windows Close browser window	`Ctrl` + `Shift` + `W` / `Alt` + `F4`
Firefox Windows Opens the title bar menu (default Windows feature)	`Alt` + `Space`
Firefox Windows Restore Window (default Windows feature)	`Alt` + `Space` + `Enter`
Firefox Windows Maximize Window (default Windows feature)	`Alt` + `Space` + `X`
Firefox Windows Minimize Window (default Windows feature)	`Alt` + `Space` + `N`
Firefox Windows Turn full page view on or off (default Windows feature)	`F11`
Forms Jump to next or previous form element	`Tab` / `Shift` + `Tab`
Forms Activate or deactivate radio buttons and check boxes	`Space`
Forms Select from a drop-down menu	`Alt` + `Arrow Down`
Forms Copy, cut or paste selected text (when working in forms)	`Ctrl` + `c` , `ctrl` + `x` and `ctrl` + `V`
Forms Select previously used form entries	`Arrow Up` / `Arrow Down`
Forms Delete previously used form entries	`Shift` + `Delete`
The Rest Open or close webpage Inspector	`Ctrl` + `Shift` + `I`
The Rest Open Java Error Console. Press escape to close	`Ctrl` + `Shift` + `J`
The Rest Firefox (online) help	`F1`