XF 1.5 Call getImageModal from other script

[grisha2217]

Hello, my task is call getImageModal function (bb_code_edit.js) from my script.

var ed = $('textarea.BbCodeWysiwygEditor').data('XenForo.BbCodeWysiwygEditor');
console.log(ed);
$form.find('.LoadImageButton').on('click', XenForo.BbCodeWysiwygEditor.prototype.getImageModal(ed));

Uncaught TypeError: ed.saveSelection is not a function