loremfill/loremfill-chrome

function send_fill_all_forms(tab) {
  chrome.tabs.sendMessage(
    tab.id,
    {
      text: 'fill_all_forms',
    },
    function() {}
  );
}

function send_fill_single_element(tab) {
  chrome.tabs.sendMessage(
    tab.id,
    {
      text: 'fill_single_element',
    },
    function() {}
  );
}

chrome.contextMenus.create({
  id: 'context_menu_lorem_fill_this_page',
  title: 'Lorem Fill this page ⌘⇧1',
  contexts: ['page'],
});

chrome.contextMenus.create({
  id: 'context_menu_lorem_fill_this_element',
  title: 'Lorem Fill this single element',
  contexts: ['editable'],
});

chrome.browserAction.onClicked.addListener(send_fill_all_forms);

chrome.contextMenus.onClicked.addListener(function(info, tab) {
  if (info.menuItemId === 'context_menu_lorem_fill_this_page') {
    send_fill_all_forms(tab);
  }
  if (info.menuItemId === 'context_menu_lorem_fill_this_element') {
    send_fill_single_element(tab);
  }
});

chrome.commands.onCommand.addListener(function(command) {
  if (command === 'trigger_fill_all_forms') {
    chrome.tabs.getSelected(function(tab) {
      send_fill_all_forms(tab);
    });
  }
});