Disappear ? not suer what you mean.
Men you can access file edit command on many ways.
Menu > File > Edit File
Press "Edit File" icon on Toolbar ( Icon num 13, next to the icon that has a Magnifying glass )
Press the Edit icon on the Button bar.. (button 4 on first row )
If you have commander styled look'n'feel press hot key F4, for Windows Explorer styled setup, it is F9
Right click or Right button double click (depending on setup. ) and from Popup menu "MultiCommander > Edit File"