When i try to upload an image this happen
Sitecake Version: 2.3.7; PHP Version: 7.1.1@Linux; User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.133 Safari/537.36; Uncaught Exception
Exception caught: (TypeError) : Cannot read property ‘length’ of undefined com.google.gwt.event.shared.UmbrellaException: Exception caught: (TypeError) : Cannot read property ‘length’ of undefined at Unknown.pd(contentmanager-0.js) at Unknown.fi(contentmanager-0.js) at Unknown.Sq(contentmanager-0.js) at Unknown.Uq(contentmanager-0.js) at Unknown.vq(contentmanager-0.js) at Unknown.eU(contentmanager-0.js) at Unknown.Zj(contentmanager-0.js) at Unknown.Qj(contentmanager-0.js) at Unknown.ak(contentmanager-0.js) at Unknown.Xj(contentmanager-0.js) at Unknown.uj(contentmanager-0.js) at Unknown.xj(contentmanager-0.js) at Unknown.eval(contentmanager-0.js) at Unknown.d(contentmanager-0.js) Caused by: com.google.gwt.core.client.JavaScriptException: (TypeError) : Cannot read property ‘length’ of undefined at Unknown._6(contentmanager-0.js) at Unknown.EX(contentmanager-0.js) at Unknown.nV(contentmanager-0.js) at Unknown.kV(contentmanager-0.js) at Unknown.H3(contentmanager-0.js) at Unknown.J3(contentmanager-0.js) at Unknown.Eq(contentmanager-0.js) at Unknown.vq(contentmanager-0.js) at Unknown.eU(contentmanager-0.js) at Unknown.Zj(contentmanager-0.js) at Unknown.Qj(contentmanager-0.js) at Unknown.ak(contentmanager-0.js) at Unknown.Xj(contentmanager-0.js) at Unknown.uj(contentmanager-0.js) at Unknown.xj(contentmanager-0.js) at Unknown.eval(contentmanager-0.js) at Unknown.d(contentmanager-0.js)