Byobu keybindings can be user defined in /usr/share/byobu/keybindings/ (or within .screenrc if byobu-export was used). The common key bindings are:
F2 - Create a new window
F3 - Move to previous window
F4 - Move to next window
F5 - Reload profile
F6 - Detach from this session
F7 - Enter copy/scrollback mode
F8 - Re-title a window
F9 - Configuration Menu
F12 - Lock this terminal
shift-F2 - Split the screen horizontally
ctrl-F2 - Split the screen vertically
shift-F3 - Shift the focus to the previous split region
shift-F4 - Shift the focus to the next split region
shift-F5 - Join all splits
ctrl-F6 - Remove this split
ctrl-F5 - Reconnect GPG and SSH sockets
shift-F6 - Detach, but do not logout
alt-pgup - Enter scrollback mode
alt-pgdn - Enter scrollback mode
Ctrl-a $ - show detailed status
Ctrl-a R - Reload profile
Ctrl-a ! - Toggle key bindings on and off
Ctrl-a k - Kill the current window
Ctrl-a ~ - Save the current window's scrollback buffer
Each window in Byobu has up to 10,000 lines of scrollback history, which you can enter and navigate using the alt-pgup and alt-pgdn keys. Exit this scrollback mode by hitting enter. You can also easily copy and paste text from scrollback mode. To do so, enter scrollback using alt-pgup or alt-pgdn, press the spacebar to start highlighting text, use up/down/left/right/pgup/pgdn to select the text, and press enter to copy the text. You can then paste the text using alt-insert or ctrl-a-].
When there is another ssh or terminal client, other than yourself, connected to this session, which has a smaller window size than yours:
Detach all clients but yourself, using this Byobu hotkey:
Alt-F6
Or run the script
/usr/lib/byobu/include/tmux-detach-all-but-current-client