Bug 42587 Left over from content assist
M3 - set preference that content assist should overwrite - open content assist on some word so that the rest of the word is indicated to be overwritten - transfer focus to the content assist widget using TAB - Esc -> overwrite indication is still there
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/link/contentassist/CompletionProposalPopup2.java
case SWT.HOME :
						newSelection= 0;
						break;
						
					case SWT.END :
						newSelection= fProposalTable.getItemCount() - 1;
						break;
						
					default :
						if (e.keyCode != SWT.MOD1 && e.keyCode != SWT.MOD2 && e.keyCode != SWT.MOD3 && e.keyCode != SWT.MOD4)
							hide();
						return true;
				}
				
				selectProposal(newSelection, smartToggle);
				
				e.doit= false;
				return false;
	
			} else {
				
				switch (key) {
					case 0x1B: 
						e.doit= false;
						hide();
						break;
						
					case '\n': 
					case '\r':