HTML Sanitization
The new Vaadin version updates the Jsoup version to 1.20.1 in which the HTML sanitization logic was modified. Some cases are now sanitized differently, for example:

Frontend Validation for Date Time Picker
The frontend validation for Date-Time Picker (@UIDateTimeField) have changed. We could not detect any negative impact for linkki applications. If you experience any unexpected behaviors, please do not hesitate to contact us.

Manual value updates in Custom Field
CustomField now has a manual update mode. If enabled, it will no longer automatically update its values when any of its contained fields change. Instead, updateValue() must be called manually, which can reduce unnecessary intermediate updates.

Upload and download Handling
A new API for file upload and download has been introduced. Users with custom components for upload or download may need to migrate to the new API. See the Vaadin documentation for details.

Static asset management with @NpmPackage
@NpmPackage is used to declare static assets from npm packages. During build time, these asset files are copied into the frontend and no theme.json entries are needed.

Improved tool tip discoverability with styling hooks
Elements with tooltips now expose a `has-tooltip' attribute. This attribute can be used to add visual indicators in CSS for when the tooltip is available.

Anchor#setHref(AbstractStreamResource) has been deprecated.
Therefore, LinkkiAnchor#setHref(AbstractStreamResource) has been deprecated as well and is marked for removal. For setting download handlers, LinkkiAnchor#setHref(DownloadHandler) should be used. For simple links, LinkkiAnchor#setHref(String) should be used.

The constructor FrontendDependencies#FrontendDependencies(ClassFinder) has been deprecated.
The constructor with full arguments FrontendDependencies#FrontendDependencies(ClassFinder, boolean, FeatureFlags, boolean) should be used instead.

In version 2.7.5, entering a value to a cell inside a table created with @UITableComponent and traversing with the tab-key results in loosing focus. Starting with 2.7.6, the behavior has been fixed.

In version 2.7.4, the linkki-bom was published incorrectly and did not contain any dependencyManagement entries. This issue affects only version 2.7.4. Starting with 2.7.5, the BOM has been fixed and works as expected.

Required fields (e.g., TextField, ComboBox) were not marked red when prefilled with an invalid value under certain conditions. This was a Vaadin bug that is fixed with this version. Note that the issue only appeared in 2.7.1 and does not affect 2.7.0.

Loading indicator of a grid is not visible if placeholder is set and the grid does not have full height.

New properties in LumoUtility: In LumoUtility new properties have been added, most notably a utility class to set flex to 1. Existing custom CSS classes can thus be replaced by the new utility class.

Setting reactEnable to false in the vaadin-maven-plugin leads to a Vite error on startup of the application due to missing vaadin-router resources.
As the react router now behaves mostly like the legacy vaadin router, it may be an option to remove the configuration and use the default react router instead.
If the configuration should be kepft, the property vaadin.react.enable needs to be set to false too. See https://vaadin.com/docs/latest/upgrading#opting-out-of-react

New annotation: @UICheckboxes
A new UI component, @UICheckboxes, is now available, providing a way to create a checkbox group for related binary choices. For more information, see here.

New annotation: @UILongField
A new UI component, @UILongField, is now available, providing a way to accept a number with data type long. For more information, see here.

@UIComboBox: Automatically focus first applicable element
If a character or word is entered into a combobox and there is only one matching element, then this element gets selected automatically.

@UILabel: support for asynchronously loaded values
UILabel has been enhanced to handle asynchronous value loading using CompletableFuture as return type. A loading indicator will be displayed until the value is available. Refer to UILabel documentation for more details.

New aspect annotation: @BindClosable for sections
A new aspect annotation, @BindClosable, is now available, providing a way to create closable sections with the option to have them initially closed. For more information, see here.

@BindPlaceholder: support for sections
The @BindPlaceholder annotation can now be used on a @UISection to set a placeholder text if the section has no child elements or all child elements are invisible.

@BindPlaceholder
@UISection(caption = "@UISection with @BindPlaceholder")
public class SectionWithBindPlaceholder {

    public String getPlaceholder() {
        return "This section is empty";
    }

}

@UISection(caption = "@UISection with placeholder label")
public class SectionWithPlaceholderLabel {

    @UILabel(position = 10, label = "", styleNames = LinkkiTheme.Text.TEXT_PLACEHOLDER)
    public String getPlaceholder() {
        return "This is a placeholder.";
    }

}

Unique IDs for exceptions
If an exception occurs in the application, it will be displayed by the configured error handler or an error page in case of an exception during navigation. With the default configuration, the exception is now logged with a unique ID that is also displayed in the UI, making it easier to find the exception in the logs. Custom implementation may need to be adapted to be able to make use of this feature.

Karibu testing: more utilities
The KaribuUIExtension has been extended with possibilities to add error routes and to set production mode. The documentation has been improved accordingly.
Many useful methods were also added to the KaribuUtils to make it even easier to write Karibu tests, such as

Testbench extension: support for table placeholder
The new page object LinkkiGridElement adds support to retrieve the placeholder text of a table. It can be used instead of GridElement, e.g. $(LinkkiGridElement.class).

Tutorial in the documentation
The linkki tutorial is now part of this documentation.

LabelComponentWrapper#setLabel() now calls HasLabel#setLabel() if the component is an instance of HasLabel instead of setting the HTML property directly.

The items of a table created with @UITableComponent are now only fetched asynchronously if the return type is CompletableFuture. The documentation is updated accordingly.

Card sections theme now only applies to dialogs if the theme is explicitly set on the dialog itself or a child layout.

The disabled and readonly style of radio buttons and checkboxes has been harmonised to follow the linkki style guidelines.

DefaultCaptionProvider now takes the provided locale into account and translates the captions accordingly.

The recommended .gitignore file is now added in generated archetype projects.

Components within a form layout that are required and have an empty/ blank label do not scroll anymore.

@UIDecimalField now handles very large numbers without unwanted rounding.

Previously, setting the value to null in @UIRadioButtons failed to check the appropriate radio button. Now, selecting null correctly checks the "Not specified" radio button, ensuring proper representation.

Disabled, readonly and checked radio buttons are now displayed correctly