Bug 213504 [Markers] Problems View no longer supports dragging into the Editor Area
I20071218-0800. You used to be able to drag an error into the Editor Area in order to open the associated file. I commonly use the DnD gesture to open a 'problem' but it appears that this isn't working in the new version...
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/ExtendedMarkersView.java
MarkerCategory[] categories = builder.getCategories();
					if (categories != null && categories.length == 1)
						getCategoriesToExpand().add(
								categories[0].getDescription());
				}
				getViewer().refresh(true);
				updateTitle();
				if (preservedSelection.size() > 0) {
					Collection newSelection = new ArrayList();
					MarkerItem[] markerEntries = builder.getMarkerEntries();
					for (int i = 0; i < markerEntries.length; i++) {
						Iterator preserved = preservedSelection.iterator();
						while (preserved.hasNext()) {
							MarkerSelectionEntry next = (MarkerSelectionEntry) preserved
									.next();
							if (next.isEquivalentTo(markerEntries[i])) {
								newSelection.add(markerEntries[i]);
								continue;
							}
						}
					}
					getViewer().setSelection(
							new StructuredSelection(newSelection.toArray()),
							true);
					preservedSelection.clear();
				}
				if (getViewer().getTree().getItemCount() > 0)
					getViewer().getTree().setTopItem(
							getViewer().getTree().getItem(0));
				reexpandCategories(builder);