diff --git a/.github/changelog/fix-comment-query-type-coexistence b/.github/changelog/fix-comment-query-type-coexistence
new file mode 100644
index 0000000000..8c096f88b1
--- /dev/null
+++ b/.github/changelog/fix-comment-query-type-coexistence
@@ -0,0 +1,4 @@
+Significance: patch
+Type: fixed
+
+Stop ActivityPub Likes, Reposts, and Quotes from leaking into the front-end comment list on sites that also use other comment-filtering plugins.
diff --git a/includes/class-comment.php b/includes/class-comment.php
index 9500377f9d..a04fbed3ff 100644
--- a/includes/class-comment.php
+++ b/includes/class-comment.php
@@ -784,18 +784,33 @@ public static function comment_query( $query ) {
 			return;
 		}
 
-		// Do not exclude likes and reposts if the query is for specific types.
-		if ( ! empty( $query->query_vars['type__in'] ) || ! empty( $query->query_vars['type'] ) ) {
-			return;
-		}
+		$ap_types = self::get_comment_type_slugs();
 
-		// Do not exclude likes and reposts if the query is already excluding other comment types.
-		if ( ! empty( $query->query_vars['type__not_in'] ) ) {
-			return;
+		/*
+		 * If the caller is explicitly asking for one of the ActivityPub
+		 * comment types (likes, reposts, …) — or for `'all'`, which WP
+		 * treats as a sentinel meaning "include everything, even types we
+		 * would normally exclude" — respect that. Otherwise we still merge
+		 * our slugs into `type__not_in`, so the AP exclusion composes with
+		 * whatever other plugins are filtering on. The previous version
+		 * bailed out as soon as any of `type__in`, `type` or `type__not_in`
+		 * was set — which let AP comments leak through on themes that use
+		 * plugins like GatherPress (which sets `type__in` for its own RSVP
+		 * filtering).
+		 */
+		foreach ( array( 'type__in', 'type' ) as $key ) {
+			if ( empty( $query->query_vars[ $key ] ) ) {
+				continue;
+			}
+
+			$requested = (array) $query->query_vars[ $key ];
+			if ( \in_array( 'all', $requested, true ) || \array_intersect( $requested, $ap_types ) ) {
+				return;
+			}
 		}
 
-		// Exclude likes and reposts by the ActivityPub plugin.
-		$query->query_vars['type__not_in'] = self::get_comment_type_slugs();
+		$existing                          = (array) ( $query->query_vars['type__not_in'] ?? array() );
+		$query->query_vars['type__not_in'] = \array_values( \array_unique( \array_merge( $existing, $ap_types ) ) );
 	}
 
 	/**
diff --git a/tests/phpunit/tests/includes/class-test-comment.php b/tests/phpunit/tests/includes/class-test-comment.php
index 639d4b2b44..d33fb8d3d2 100644
--- a/tests/phpunit/tests/includes/class-test-comment.php
+++ b/tests/phpunit/tests/includes/class-test-comment.php
@@ -907,6 +907,110 @@ public function test_post_comments_filtered_by_type__not_in() {
 		$this->assertNotContains( (string) $comment_id, $comment_ids, 'AP post comment should be hidden even when querying specific post' );
 	}
 
+	/**
+	 * Test that AP exclusion composes with a caller's existing `type__in`.
+	 *
+	 * Regression for #3306: GatherPress sets `type__in` for its own RSVP
+	 * filtering, which previously caused `comment_query` to bail out, and
+	 * AP comment types leaked into the front-end comment list. The new
+	 * behavior merges AP slugs into `type__not_in` whenever `type__in`
+	 * does not request an AP type.
+	 *
+	 * @covers ::comment_query
+	 */
+	public function test_comment_query_merges_ap_exclusion_with_existing_type_in() {
+		$post_id = self::factory()->post->create();
+		$this->go_to( \get_permalink( $post_id ) );
+
+		$this->assertTrue( \is_singular(), 'Sanity: test setup must reach the singular branch.' );
+
+		$query             = new \WP_Comment_Query();
+		$query->query_vars = array( 'type__in' => array( 'gatherpress_rsvp' ) );
+
+		\Activitypub\Comment::comment_query( $query );
+
+		$this->assertSame( array( 'gatherpress_rsvp' ), $query->query_vars['type__in'] );
+		$this->assertArrayHasKey( 'type__not_in', $query->query_vars );
+		$this->assertContains( 'like', $query->query_vars['type__not_in'] );
+		$this->assertContains( 'repost', $query->query_vars['type__not_in'] );
+	}
+
+	/**
+	 * Test that AP exclusion composes with a caller's existing `type__not_in`.
+	 *
+	 * @covers ::comment_query
+	 */
+	public function test_comment_query_merges_ap_exclusion_with_existing_type_not_in() {
+		$post_id = self::factory()->post->create();
+		$this->go_to( \get_permalink( $post_id ) );
+
+		$query             = new \WP_Comment_Query();
+		$query->query_vars = array( 'type__not_in' => array( 'pingback' ) );
+
+		\Activitypub\Comment::comment_query( $query );
+
+		$this->assertContains( 'pingback', $query->query_vars['type__not_in'] );
+		$this->assertContains( 'like', $query->query_vars['type__not_in'] );
+		$this->assertContains( 'repost', $query->query_vars['type__not_in'] );
+	}
+
+	/**
+	 * Test that an explicit request for an AP comment type is respected.
+	 *
+	 * @covers ::comment_query
+	 */
+	public function test_comment_query_respects_explicit_ap_type_request() {
+		$post_id = self::factory()->post->create();
+		$this->go_to( \get_permalink( $post_id ) );
+
+		$query             = new \WP_Comment_Query();
+		$query->query_vars = array( 'type__in' => array( 'like' ) );
+
+		\Activitypub\Comment::comment_query( $query );
+
+		$this->assertTrue(
+			empty( $query->query_vars['type__not_in'] ),
+			'Caller is explicitly asking for AP likes; we must not add likes to type__not_in.'
+		);
+	}
+
+	/**
+	 * Test that the WordPress `'all'` sentinel disables AP exclusion.
+	 *
+	 * WP_Comment_Query treats `type => 'all'` and `type__in => array('all')`
+	 * as "include everything, even types we'd normally hide" (e.g. the
+	 * built-in `note` exclusion is also disabled in that case). Our filter
+	 * has to honor the same sentinel, otherwise a caller asking for the
+	 * full set still can't see ActivityPub Likes / Reposts / Quotes.
+	 *
+	 * @covers ::comment_query
+	 */
+	public function test_comment_query_respects_all_sentinel() {
+		$post_id = self::factory()->post->create();
+		$this->go_to( \get_permalink( $post_id ) );
+
+		$query             = new \WP_Comment_Query();
+		$query->query_vars = array( 'type' => 'all' );
+
+		\Activitypub\Comment::comment_query( $query );
+
+		$this->assertTrue(
+			empty( $query->query_vars['type__not_in'] ),
+			"Caller passed `type => 'all'`; AP slugs must not be appended to type__not_in."
+		);
+
+		// Same again via `type__in`.
+		$query             = new \WP_Comment_Query();
+		$query->query_vars = array( 'type__in' => array( 'all' ) );
+
+		\Activitypub\Comment::comment_query( $query );
+
+		$this->assertTrue(
+			empty( $query->query_vars['type__not_in'] ),
+			"Caller passed `type__in => array('all')`; AP slugs must not be appended to type__not_in."
+		);
+	}
+
 	/**
 	 * Test auto-approving comments on ap_post when option is enabled.
 	 *