diff --git a/tests/phpunit/data/themedir1/fse/theme.json b/tests/phpunit/data/themedir1/fse/theme.json
index bda2c76463..b6452a9369 100644
--- a/tests/phpunit/data/themedir1/fse/theme.json
+++ b/tests/phpunit/data/themedir1/fse/theme.json
@@ -14,7 +14,32 @@
 					"color": "#000"
 				}
 			],
-			"custom": false
+			"gradients": [
+				{
+					"name": "Custom gradient",
+					"gradient": "linear-gradient(135deg,rgba(0,0,0) 0%,rgb(0,0,0) 100%)",
+					"slug": "custom-gradient"
+				}
+			],
+			"custom": false,
+			"customGradient": false
+		},
+		"typography": {
+			"fontSizes": [
+				{
+					"name": "Custom",
+					"slug": "custom",
+					"size": "100px"
+				}
+			],
+			"customFontSize": false,
+			"customLineHeight": true
+		},
+		"spacing": {
+			"units": [
+				"rem"
+			],
+			"customPadding": true
 		},
 		"blocks": {
 			"core/paragraph": {
diff --git a/tests/phpunit/tests/blocks/block-editor.php b/tests/phpunit/tests/blocks/block-editor.php
index 4d4fe7b3b5..b1bda39abd 100644
--- a/tests/phpunit/tests/blocks/block-editor.php
+++ b/tests/phpunit/tests/blocks/block-editor.php
@@ -343,6 +343,70 @@ class WP_Test_Block_Editor extends WP_UnitTestCase {
 		$this->assertSame( 12345, $settings['maxUploadFileSize'] );
 	}
 
+	/**
+	 * @ticket 53458
+	 */
+	function test_get_block_editor_settings_theme_json_settings() {
+		switch_theme( 'fse' );
+
+		$post_editor_context = new WP_Block_Editor_Context( array( 'post' => get_post() ) );
+
+		$settings = get_block_editor_settings( array(), $post_editor_context );
+
+		// Related entry in theme.json: settings.color.palette
+		$this->assertSameSetsWithIndex(
+			array(
+				array(
+					'slug'  => 'light',
+					'name'  => 'Light',
+					'color' => '#f5f7f9',
+				),
+				array(
+					'slug'  => 'dark',
+					'name'  => 'Dark',
+					'color' => '#000',
+				),
+			),
+			$settings['colors']
+		);
+		// settings.color.gradients
+		$this->assertSameSetsWithIndex(
+			array(
+				array(
+					'name'     => 'Custom gradient',
+					'gradient' => 'linear-gradient(135deg,rgba(0,0,0) 0%,rgb(0,0,0) 100%)',
+					'slug'     => 'custom-gradient',
+				),
+			),
+			$settings['gradients']
+		);
+		// settings.typography.fontSizes
+		$this->assertSameSetsWithIndex(
+			array(
+				array(
+					'name' => 'Custom',
+					'slug' => 'custom',
+					'size' => '100px',
+				),
+			),
+			$settings['fontSizes']
+		);
+		// settings.color.custom
+		$this->assertTrue( $settings['disableCustomColors'] );
+		// settings.color.customGradient
+		$this->assertTrue( $settings['disableCustomGradients'] );
+		// settings.typography.customFontSize
+		$this->assertTrue( $settings['disableCustomFontSizes'] );
+		// settings.typography.customLineHeight
+		$this->assertTrue( $settings['enableCustomLineHeight'] );
+		// settings.spacing.enableCustomUnits
+		$this->assertSameSets( array( 'rem' ), $settings['enableCustomUnits'] );
+		// settings.spacing.customPadding
+		$this->assertTrue( $settings['enableCustomSpacing'] );
+
+		switch_theme( WP_DEFAULT_THEME );
+	}
+
 	/**
 	 * @ticket 52920
 	 * @expectedDeprecated block_editor_settings
diff --git a/tests/phpunit/tests/theme/wpThemeJsonResolver.php b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
index 469aca1b4e..4923a1b636 100644
--- a/tests/phpunit/tests/theme/wpThemeJsonResolver.php
+++ b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
@@ -108,8 +108,8 @@ class Tests_Theme_wpThemeJsonResolver extends WP_UnitTestCase {
 		$this->assertSame( wp_get_theme()->get( 'TextDomain' ), 'fse' );
 		$this->assertSame(
 			array(
-				'color'  => array(
-					'palette' => array(
+				'color'      => array(
+					'palette'        => array(
 						'theme' => array(
 							array(
 								'slug'  => 'light',
@@ -123,9 +123,38 @@ class Tests_Theme_wpThemeJsonResolver extends WP_UnitTestCase {
 							),
 						),
 					),
-					'custom'  => false,
+					'gradients'      => array(
+						'theme' => array(
+							array(
+								'name'     => 'Custom gradient',
+								'gradient' => 'linear-gradient(135deg,rgba(0,0,0) 0%,rgb(0,0,0) 100%)',
+								'slug'     => 'custom-gradient',
+							),
+						),
+					),
+					'custom'         => false,
+					'customGradient' => false,
 				),
-				'blocks' => array(
+				'typography' => array(
+					'fontSizes'        => array(
+						'theme' => array(
+							array(
+								'name' => 'Custom',
+								'slug' => 'custom',
+								'size' => '100px',
+							),
+						),
+					),
+					'customFontSize'   => false,
+					'customLineHeight' => true,
+				),
+				'spacing'    => array(
+					'units'         => array(
+						'rem',
+					),
+					'customPadding' => true,
+				),
+				'blocks'     => array(
 					'core/paragraph' => array(
 						'color' => array(
 							'palette' => array(