Make ⌘-Enter submit tweets in Twitter.

twitter.com.js

DotJs = {
  is_command_pressed : false,

  is_command_key : function (event) {
    return (event.which === 91 || event.which === 93);
  }
};

$(document).
  on("keydown", function(event) {
    if (DotJs.is_command_key(event)) {
      DotJs.is_command_pressed = true; }
  }).
  on("keyup", function (event) {
    if (DotJs.is_command_key(event)) {
      DotJs.is_command_pressed = false; }
  }).
  on("keydown", function (event) {
    if (event.which === 13 && DotJs.is_command_pressed) {
      $(event.target).parents(".tweet-form").find('.tweet-action').click();
    }
  });