• Added craft\services\Security::isSystemDir().
• Fixed a bug where craft\helpers\StringHelper::lines() was returning an array of Stringy\Stringy objects, rather than strings.
• Fixed styling issues with Template field layout UI elements’ selector labels.
• Fixed a validation error that could occur when saving a relational field, if the “Maintain hierarchy” setting had been enabled but was no longer applicable. (#15666)
• Fixed a bug where formatted addresses weren’t using the application locale consistently. (#15668)
• Fixed a bug where Tip and Warning field layout UI elements would display in field layouts even if they had no content. (#15681)
• Fixed an error that could occur when reverting an element’s content from a revision, if the element had been added to additional sites since the time the revision was created. (#15679)
• Fixed an information disclosure vulnerability.