Bug 110087 [Markers] "Filters" menu doesn't remember the last selected filter
When I was playing with this it was a true pain. I'd change somes ettings to see what effect it had and then re-open the dialog to try some other settings I had to re-select my filter (it selects the first one always)...
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/provisional/views/markers/FiltersConfigurationDialog.java
* (non-Javadoc)
							 * 
							 * @see org.eclipse.jface.dialogs.IInputValidator#isValid(java.lang.String)
							 */
							public String isValid(String newText) {
								if (newText.length() == 0)
									return MarkerMessages.MarkerFilterDialog_emptyMessage;
								Iterator filterIterator = filterGroups
										.iterator();
								while (filterIterator.hasNext()) {
									if (((MarkerFieldFilterGroup) filterIterator
											.next()).getName().equals(newText))
										return NLS
												.bind(
														MarkerMessages.filtersDialog_conflictingName,
														newText);
								}
								return null;
							}
						});
				newDialog.open();
				String newName = newDialog.getValue();
				if (newName != null) {
					createNewFilter(newName);
				}
			}
		});
		setButtonLayoutData(addNew);
		removeButton = new Button(buttons, SWT.PUSH);
		removeButton.setText(MarkerMessages.MarkerFilter_deleteSelectedName);