Grid: Add Filter that ignores special characters?

I have a grid containing data that might have special characters (e.g. á, ö, é).
I already configured my columns so that, when sorted, the grid will know to ignore and treat the special characters like normal (e.g. a, o, e)

Collator insenstiveStringComparator = Collator.getInstance();
insenstiveStringComparator.setStrength(Collator.PRIMARY);
grid.addColumn(Person::getLast_name)
    .setHeader("Last Name")
	.setComparator((person1, person2) -> insenstiveStringComparator.compare(person1.getLast_name().toLowerCase(), person2.getLast_name().toLowerCase()));

What can be done so that the same idea can be done for a Filter Row?

For example, what I currently have ignores special the special character é if I type in e in the Filter TextField:

TextField field = new TextField();
ValueProvider<Person, String> valueProvider = iterator2.next();
field.addValueChangeListener(event -> {
	dataProvider.addFilter(person -> StringUtils.containsIgnoreCase(
                valueProvider.apply(person), field.getValue()));});

field.setValueChangeMode(ValueChangeMode.EAGER);

filterRow.getCell(column).setComponent(field);
field.setSizeFull();
field.setPlaceholder("Filter");

If I understand correctly what you’re trying to do, you’ll could apply an additional method call that normalizes the results from valueProvider.apply and field.getValue. This StackOverflow question might provide additional hints: https://stackoverflow.com/questions/32696273/java-replace-german-umlauts

You’re exactly right - I just needed to add an extra step in that portion of the dataProvider.addFilter method call. Thanks!