Please enable multiple symbol selection in QuoteGrid, and add cut/copy/paste to right-click context menu.
Consider this proposed functionality :
1) I am in Portfolio1 QuoteGrid, and I select one symbol by click, or multiple symbols (by ctrl-click) ;
2) I right-click and now have the (new) ability to copy these to clipboard (or delete/cut them from QuoteGrid);
3) I move to Portfolio2 QuoteGrid (another portfolio window) - and I can paste symbols from clipboard to QuoteGrid.
Thanks for considering these suggestions.