text: Title: Dragging a data file to canvas should retain file history in the File widget
  Body: **What's wrong?**
  
  A nice feature of Orange is a shortcut to open data files by dragging the file to the Orange canvas. This places a File widget on a canvas, and sets the name of the file accordingly. The only problem with this feature is that it empties all the file history that File widget keeps, including the initial history with the files that came with Orange. Especially when using Orange in hands-on workshops, removal of the file history with preloaded files does not help.
  
  **How can we reproduce the problem?** 
  
  Open Orange and drag any excel file to the Canvas.
  
  **Proposal for solution** 
  
  File widget should open the dragged file, but also keep the file history.
  
  **Comment**
  
  Perhaps this is not the bug, but rather an implementational feature, and if, treat this issue as feature request.