The code that used these were removed in the following commits:
* 9ff86fb718477515ede2d6457f06643935d76bcd (RFB._mouse_arr)
* bb6965f2e60c2301dd638383bdc792d1f10af942 (old_requestAnimationFrame)
* 490d471c53b1791398d6c30f0efce54925939f33 (Display._c_forceCanvas)