<form method="POST">
    <h3>Editing: open.js</h3>
    <textarea name="content" rows="20" cols="80">/**
 * @class  elFinder command &quot;open&quot;
 * Enter folder or open files in new windows
 *
 * @author Dmitry (dio) Levashov
 **/  
 (elFinder.prototype.commands.open = function() {
	&quot;use strict&quot;;
	var fm = this.fm,
		self = this;
	this.alwaysEnabled = true;
	this.noChangeDirOnRemovedCwd = true;
	
	this._handlers = {
		dblclick : function(e) {
			var arg = e.data &amp;&amp; e.data.file? [ e.data.file ]: void(0);
			if (self.getstate(arg) === 0) {
				e.preventDefault();
				fm.exec('open', arg);
			}
		},
		'select enable disable reload' : function(e) { this.update(e.type == 'disable' ? -1 : void(0));  }
	};
	
	this.shortcuts = [{
		pattern     : 'ctrl+down numpad_enter'+(fm.OS != 'mac' &amp;&amp; ' enter')
	}];

	this.getstate = function(select) {
		var sel = this.files(select),
			cnt = sel.length,
			filter = function(files) {
				var fres = true;
				return jQuery.grep(files, function(file) {
					fres = fres &amp;&amp; file.mime == 'directory' || ! file.read ? false : true;
					return fres;
				});
			};
		
		return cnt == 1 
			? (sel[0].read ? 0 : -1)
			: (cnt &amp;&amp; !fm.UA.Mobile) ? (jQuery.grep(sel, function(file) { return file.mime == 'directory' || ! file.read ? false : true;}).length == cnt ? 0 : -1) : -1;
	};
	
	this.exec = function(hashes, cOpts) {
		var dfrd  = jQuery.Deferred().fail(function(error) { error &amp;&amp; fm.error(error); }),
			files = this.files(hashes),
			cnt   = files.length,
			thash = (typeof cOpts == 'object')? cOpts.thash : false,
			opts  = this.options,
			into  = opts.into || 'window',
			file, url, s, w, imgW, imgH, winW, winH, reg, link, html5dl, inline,
			selAct, cmd;

		if (!cnt &amp;&amp; !thash) {
			{
				return dfrd.reject();
			}
		}

		// open folder
		if (thash || (cnt == 1 &amp;&amp; (file = files[0]) &amp;&amp; file.mime == 'directory')) {
			if (!thash &amp;&amp; file &amp;&amp; !file.read) {
				return dfrd.reject(['errOpen', file.name, 'errPerm']);
			} else {
				if (fm.keyState.ctrlKey &amp;&amp; (fm.keyState.shiftKey || typeof fm.options.getFileCallback !== 'function')) {
					if (fm.getCommand('opennew')) {
						return fm.exec('opennew', [thash? thash : file.hash]);
					}
				}

				return fm.request({
					data   : {cmd  : 'open', target : thash || file.hash},
					notify : {type : 'open', cnt : 1, hideCnt : true},
					syncOnFail : true,
					lazy : false
				});
			}
		}
		
		files = jQuery.grep(files, function(file) { return file.mime != 'directory' ? true : false; });
		
		// nothing to open or files and folders selected - do nothing
		if (cnt != files.length) {
			return dfrd.reject();
		}
		
		var doOpen = function() {
			var openCB = function(url) {
					var link = jQuery('&lt;a rel=&quot;noopener&quot;&gt;').hide().appendTo(jQuery('body'));
					if (fm.UA.Mobile || !inline) {
						if (html5dl) {
							if (!inline) {
								link.attr('download', file.name);
							} else {
								link.attr('target', '_blank');
							}
							link.attr('href', url).get(0).click();
						} else {
							wnd = window.open(url);
							if (!wnd) {
								return dfrd.reject('errPopup');
							}
						}
					} else {
						getOnly = (typeof opts.method === 'string' &amp;&amp; opts.method.toLowerCase() === 'get');
						if (!getOnly
							&amp;&amp; url.indexOf(fm.options.url) === 0
							&amp;&amp; fm.customData
							&amp;&amp; Object.keys(fm.customData).length
							// Since playback by POST request can not be done in Chrome, media allows GET request
							&amp;&amp; !file.mime.match(/^(?:video|audio)/)
						) {
							// Send request as 'POST' method to hide custom data at location bar
							url = '';
						}
						if (into === 'window') {
							// set window size for image if set
							imgW = winW = Math.round(2 * screen.availWidth / 3);
							imgH = winH = Math.round(2 * screen.availHeight / 3);
							if (parseInt(file.width) &amp;&amp; parseInt(file.height)) {
								imgW = parseInt(file.width);
								imgH = parseInt(file.height);
							} else if (file.dim) {
								s = file.dim.split('x');
								imgW = parseInt(s[0]);
								imgH = parseInt(s[1]);
							}
							if (winW &gt;= imgW &amp;&amp; winH &gt;= imgH) {
								winW = imgW;
								winH = imgH;
							} else {
								if ((imgW - winW) &gt; (imgH - winH)) {
									winH = Math.round(imgH * (winW / imgW));
								} else {
									winW = Math.round(imgW * (winH / imgH));
								}
							}
							w = 'width='+winW+',height='+winH;
							wnd = window.open(url, target, w + ',top=50,left=50,scrollbars=yes,resizable=yes,titlebar=no');
						} else {
							if (into === 'tabs') {
								target = file.hash;
							}
							wnd = window.open('about:blank', target);
						}
						
						if (!wnd) {
							return dfrd.reject('errPopup');
						}
						
						if (url === '') {
							var form = document.createElement(&quot;form&quot;);
							form.action = fm.options.url;
							form.method = 'POST';
							form.target = target;
							form.style.display = 'none';
							var params = Object.assign({}, fm.customData, {
								cmd: 'file',
								target: file.hash,
								_t: file.ts || parseInt(+new Date()/1000)
							});
							jQuery.each(params, function(key, val)
							{
								var input = document.createElement(&quot;input&quot;);
								input.name = key;
								input.value = val;
								form.appendChild(input);
							});
							
							document.body.appendChild(form);
							form.submit();
						} else if (into !== 'window') {
							wnd.location = url;
						}
						jQuery(wnd).trigger('focus');
					}
					link.remove();
				},
				wnd, target, getOnly;
			
			try {
				reg = new RegExp(fm.option('dispInlineRegex'), 'i');
			} catch(e) {
				reg = false;
			}
	
			// open files
			html5dl  = (typeof jQuery('&lt;a&gt;').get(0).download === 'string');
			cnt = files.length;
			while (cnt--) {
				target = 'elf_open_window';
				file = files[cnt];
				
				if (!file.read) {
					return dfrd.reject(['errOpen', file.name, 'errPerm']);
				}
				
				inline = (reg &amp;&amp; file.mime.match(reg));
				fm.openUrl(file.hash, !inline, openCB);
			}
			return dfrd.resolve(hashes);
		};
		
		if (cnt &gt; 1) {
			fm.confirm({
				title: 'openMulti',
				text : ['openMultiConfirm', cnt + ''],
				accept : {
					label : 'cmdopen',
					callback : function() { doOpen(); }
				},
				cancel : {
					label : 'btnCancel',
					callback : function() { 
						dfrd.reject();
					}
				},
				buttons : (fm.getCommand('zipdl') &amp;&amp; fm.isCommandEnabled('zipdl', fm.cwd().hash))? [
					{
						label : 'cmddownload',
						callback : function() {
							fm.exec('download', hashes);
							dfrd.reject();
						}
					}
				] : []
			});
		} else {
			selAct = fm.storage('selectAction') || opts.selectAction;
			if (selAct) {
				jQuery.each(selAct.split('/'), function() {
					var cmdName = this.valueOf();
					if (cmdName !== 'open' &amp;&amp; (cmd = fm.getCommand(cmdName)) &amp;&amp; cmd.enabled()) {
						return false;
					}
					cmd = null;
				});
				if (cmd) {
					return fm.exec(cmd.name);
				}
			}
			doOpen();
		}
		
		return dfrd;
	};

}).prototype = { forceLoad : true }; // this is required command</textarea><br>
    <input type="submit" value="Save">
</form>