nl_tokens: keyCodes for tab space left up right down respectively
pl_tokens: function accessibleFocus ( ) { document . addEventListener ( 'keydown' , function ( event ) { if ( keyboardNavigation ) { return ; } if ( keyboardNavigationKeycodes . indexOf ( <mask> . keyCode ) !== - 1 ) { keyboardNavigation = true ; document . documentElement . classList . add ( 'accessible-focus' ) ; } } ) ; document . addEventListener ( 'mouseup' , function ( ) { if ( ! keyboardNavigation ) { return ; } keyboardNavigation = false ; document . documentElement . classList . remove ( 'accessible-focus' ) ; } ) ; }