diff --git a/Tests/Unit/classes/Picture/BuildPictureTagTest.php b/Tests/Unit/classes/Picture/BuildPictureTagTest.php
new file mode 100644
index 000000000..6598e8bdf
--- /dev/null
+++ b/Tests/Unit/classes/Picture/BuildPictureTagTest.php
@@ -0,0 +1,189 @@
+<?php
+declare(strict_types=1);
+
+namespace Imagify\Tests\Unit\classes\Picture;
+
+use Brain\Monkey\Functions;
+use Imagify\Picture\Display;
+use Imagify\Tests\Unit\TestCase;
+use ReflectionClass;
+
+/**
+ * Tests for \Imagify\Picture\Display::build_picture_tag().
+ *
+ * @covers \Imagify\Picture\Display::build_picture_tag
+ * @group  PictureDisplayBuildPictureTag
+ * @since  2.3.1
+ */
+class BuildPictureTagTest extends TestCase {
+
+	/**
+	 * Set up the test environment.
+	 */
+	protected function setUp(): void {
+		parent::setUp();
+
+		Functions\when( 'esc_attr' )->returnArg();
+	}
+
+	/**
+	 * Get an instance of Display without invoking the constructor (its only
+	 * dependency, Imagify_Filesystem, is not needed by build_picture_tag()).
+	 *
+	 * @return Display
+	 */
+	private function get_display_instance(): Display {
+		$reflection = new ReflectionClass( Display::class );
+
+		return $reflection->newInstanceWithoutConstructor();
+	}
+
+	/**
+	 * Build a minimal $image array as expected by build_picture_tag(), build_source_tag()
+	 * and build_img_tag(). $attributes is the raw <img> attributes array.
+	 *
+	 * @param array $attributes The <img> attributes.
+	 *
+	 * @return array
+	 */
+	private function get_image_data( array $attributes ): array {
+		return [
+			'attributes'       => $attributes,
+			'src_attribute'    => 'src',
+			'srcset_attribute' => false,
+			'srcset'           => [],
+			'src'              => [],
+		];
+	}
+
+	/**
+	 * Extract the opening <picture ...> tag's attribute string from the built output.
+	 *
+	 * @param string $output The output of build_picture_tag().
+	 *
+	 * @return string
+	 */
+	private function get_picture_opening_tag( string $output ): string {
+		preg_match( '/^<picture([^>]*)>/', $output, $matches );
+
+		return $matches[1] ?? '';
+	}
+
+	/**
+	 * Extract the <img .../> tag's attribute string from the built output.
+	 *
+	 * @param string $output The output of build_picture_tag().
+	 *
+	 * @return string
+	 */
+	private function get_img_tag( string $output ): string {
+		preg_match( '/<img([^>]*)\/>/', $output, $matches );
+
+		return $matches[1] ?? '';
+	}
+
+	/**
+	 * `data-wp-*` directive attributes must be filtered out of the <picture> tag,
+	 * but kept on the inner <img> tag.
+	 */
+	public function testDataWpAttributesAreExcludedFromPictureTagButKeptOnImgTag(): void {
+		$attributes = [
+			'data-object-fit'     => 'cover',
+			'data-wp-interactive' => 'core/image',
+			'data-wp-context'     => '{"isOpen":false}',
+			'data-wp-on--click'   => 'actions.showLightbox',
+		];
+
+		$image = $this->get_image_data( $attributes );
+
+		$method = $this->get_reflective_method( 'build_picture_tag', Display::class );
+		$output = $method->invoke( $this->get_display_instance(), $image );
+
+		$picture_tag = $this->get_picture_opening_tag( $output );
+		$img_tag     = $this->get_img_tag( $output );
+
+		$this->assertStringNotContainsString( 'data-wp-interactive', $picture_tag );
+		$this->assertStringNotContainsString( 'data-wp-context', $picture_tag );
+		$this->assertStringNotContainsString( 'data-wp-on--click', $picture_tag );
+
+		$this->assertStringContainsString( 'data-wp-interactive="core/image"', $img_tag );
+		$this->assertStringContainsString( 'data-wp-context="{"isOpen":false}"', $img_tag );
+		$this->assertStringContainsString( 'data-wp-on--click="actions.showLightbox"', $img_tag );
+	}
+
+	/**
+	 * Non `data-wp` attributes are unaffected by the new filter and keep behaving
+	 * as they did before: they remain on the <picture> tag, and follow the
+	 * pre-existing removal rules on the <img> tag.
+	 */
+	public function testNonDataWpAttributesAreUnaffected(): void {
+		$attributes = [
+			'data-object-fit' => 'cover',
+			'class'           => 'my-image',
+			'id'              => 'img-1',
+		];
+
+		$image = $this->get_image_data( $attributes );
+
+		$method = $this->get_reflective_method( 'build_picture_tag', Display::class );
+		$output = $method->invoke( $this->get_display_instance(), $image );
+
+		$picture_tag = $this->get_picture_opening_tag( $output );
+		$img_tag     = $this->get_img_tag( $output );
+
+		// All 3 attributes remain on the <picture> tag, since none of them contain 'data-wp'.
+		$this->assertStringContainsString( 'data-object-fit="cover"', $picture_tag );
+		$this->assertStringContainsString( 'class="my-image"', $picture_tag );
+		$this->assertStringContainsString( 'id="img-1"', $picture_tag );
+
+		// Pre-existing logic (unrelated to this fix) strips class/id from the <img> tag,
+		// but keeps data-object-fit.
+		$this->assertStringContainsString( 'data-object-fit="cover"', $img_tag );
+		$this->assertStringNotContainsString( 'class=', $img_tag );
+		$this->assertStringNotContainsString( 'id=', $img_tag );
+	}
+
+	/**
+	 * The new `data-wp` filter composes correctly with the pre-existing
+	 * 'wp-block-cover__image-background' exclusion logic: both sets of
+	 * attributes are removed from the <picture> tag, while the <img> tag
+	 * (which is treated as a Gutenberg cover background image) keeps
+	 * everything, including the `data-wp` attributes.
+	 */
+	public function testDataWpFilterComposesWithGutenbergCoverExclusion(): void {
+		$attributes = [
+			'class'                => 'wp-block-cover__image-background',
+			'style'                => 'object-fit:cover',
+			'data-object-fit'      => 'cover',
+			'data-object-position' => '50% 50%',
+			'data-wp-interactive'  => 'core/image',
+			'data-wp-context'      => '{}',
+		];
+
+		$image = $this->get_image_data( $attributes );
+
+		$method = $this->get_reflective_method( 'build_picture_tag', Display::class );
+		$output = $method->invoke( $this->get_display_instance(), $image );
+
+		$picture_tag = $this->get_picture_opening_tag( $output );
+		$img_tag     = $this->get_img_tag( $output );
+
+		// None of the Gutenberg-specific attributes, nor the data-wp attributes, remain on <picture>.
+		$this->assertStringNotContainsString( 'class=', $picture_tag );
+		$this->assertStringNotContainsString( 'style=', $picture_tag );
+		$this->assertStringNotContainsString( 'data-object-fit', $picture_tag );
+		$this->assertStringNotContainsString( 'data-object-position', $picture_tag );
+		$this->assertStringNotContainsString( 'data-wp-interactive', $picture_tag );
+		$this->assertStringNotContainsString( 'data-wp-context', $picture_tag );
+		$this->assertSame( '', trim( $picture_tag ) );
+
+		// The <img> tag, being the Gutenberg cover background image, keeps everything
+		// (only 'id' and 'title' are ever stripped from it in that branch).
+		$this->assertStringContainsString( 'class="wp-block-cover__image-background"', $img_tag );
+		$this->assertStringContainsString( 'style="object-fit:cover"', $img_tag );
+		$this->assertStringContainsString( 'data-object-fit="cover"', $img_tag );
+		$this->assertStringContainsString( 'data-object-position="50% 50%"', $img_tag );
+		$this->assertStringContainsString( 'data-wp-interactive="core/image"', $img_tag );
+		$this->assertStringContainsString( 'data-wp-context="{}"', $img_tag );
+	}
+}
diff --git a/classes/Picture/Display.php b/classes/Picture/Display.php
index 38848e874..c2bc2ff49 100644
--- a/classes/Picture/Display.php
+++ b/classes/Picture/Display.php
@@ -218,7 +218,15 @@ protected function build_picture_tag( $image ) {
 			unset( $attributes['data-object-position'] );
 		}
 
-		$output = '<picture' . $this->build_attributes( $attributes ) . ">\n";
+		$picture_attributes = array_filter(
+			$attributes,
+			function ( $attribute ) {
+				return strpos( $attribute, 'data-wp' ) === false;
+			},
+			ARRAY_FILTER_USE_KEY
+		);
+
+		$output = '<picture' . $this->build_attributes( $picture_attributes ) . ">\n";
 		/**
 		 * Allow to add more <source> tags to the <picture> tag.
 		 *