A fix for firefox title bar buttons when you want them to be on the left hand side.

userChrome.css

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");

/* button box to the left */
#TabsToolbar      { direction: rtl }
/* tabs ltr again */
#titlebar-content { direction: rtl }
/* buttons inverted */
#tabbrowser-tabs  { direction: ltr }
/* keep these ltr */
#titlebar-max,
#alltabs-button,
#new-tab-button,
#sync-button {
   -moz-box-ordinal-group: 0;
}
/* fix margins */
#titlebar-close { margin-right: 6px }
/* remove buttons for maximized window */
#main-window[sizemode="maximized"] .titlebar-button {
  visibility: hidden;
}
#main-window[sizemode="maximized"] #titlebar-buttonbox {
  pointer-events: none;
}
#main-window[sizemode="maximized"] .titlebar-placeholder {
    width: 0 !important;
}