diff --git a/src/wp-includes/kses.php b/src/wp-includes/kses.php
index 6308773c95..2be0b5e14c 100644
--- a/src/wp-includes/kses.php
+++ b/src/wp-includes/kses.php
@@ -2224,12 +2224,14 @@ function kses_init() {
  * @since 5.1.0 Added support for `text-transform`.
  * @since 5.2.0 Added support for `background-position` and `grid-template-columns`.
  * @since 5.3.0 Added support for `grid`, `flex` and `column` layout properties.
- *              Extend `background-*` support of individual properties.
+ *              Extended `background-*` support for individual properties.
  * @since 5.3.1 Added support for gradient backgrounds.
  * @since 5.7.1 Added support for `object-position`.
  * @since 5.8.0 Added support for `calc()` and `var()` values.
  * @since 6.1.0 Added support for `min()`, `max()`, `minmax()`, `clamp()`,
  *              and nested `var()` values.
+ *              Added support for `gap`, `column-gap`, `row-gap`, and `flex-wrap`.
+ *              Extended `margin-*` and `padding-*` support for logical properties.
  *
  * @param string $css        A string of CSS rules.
  * @param string $deprecated Not used.
@@ -2335,12 +2337,20 @@ function safecss_filter_attr( $css, $deprecated = '' ) {
 			'margin-bottom',
 			'margin-left',
 			'margin-top',
+			'margin-block-start',
+			'margin-block-end',
+			'margin-inline-start',
+			'margin-inline-end',
 
 			'padding',
 			'padding-right',
 			'padding-bottom',
 			'padding-left',
 			'padding-top',
+			'padding-block-start',
+			'padding-block-end',
+			'padding-inline-start',
+			'padding-inline-end',
 
 			'flex',
 			'flex-basis',
@@ -2348,6 +2358,11 @@ function safecss_filter_attr( $css, $deprecated = '' ) {
 			'flex-flow',
 			'flex-grow',
 			'flex-shrink',
+			'flex-wrap',
+
+			'gap',
+			'column-gap',
+			'row-gap',
 
 			'grid-template-columns',
 			'grid-auto-columns',
diff --git a/tests/phpunit/tests/kses.php b/tests/phpunit/tests/kses.php
index 3f5395fd92..274c5aaf7b 100644
--- a/tests/phpunit/tests/kses.php
+++ b/tests/phpunit/tests/kses.php
@@ -936,6 +936,7 @@ EOF;
 	 * @ticket 42729
 	 * @ticket 48376
 	 * @ticket 55966
+	 * @ticket 56122
 	 * @dataProvider data_test_safecss_filter_attr
 	 *
 	 * @param string $css      A string of CSS rules.
@@ -1034,8 +1035,8 @@ EOF;
 			),
 			// `flex` and related attributes introduced in 5.3.
 			array(
-				'css'      => 'flex: 0 1 auto;flex-basis: 75%;flex-direction: row-reverse;flex-flow: row-reverse nowrap;flex-grow: 2;flex-shrink: 1',
-				'expected' => 'flex: 0 1 auto;flex-basis: 75%;flex-direction: row-reverse;flex-flow: row-reverse nowrap;flex-grow: 2;flex-shrink: 1',
+				'css'      => 'flex: 0 1 auto;flex-basis: 75%;flex-direction: row-reverse;flex-flow: row-reverse nowrap;flex-grow: 2;flex-shrink: 1;flex-wrap: nowrap',
+				'expected' => 'flex: 0 1 auto;flex-basis: 75%;flex-direction: row-reverse;flex-flow: row-reverse nowrap;flex-grow: 2;flex-shrink: 1;flex-wrap: nowrap',
 			),
 			// `grid` and related attributes introduced in 5.3.
 			array(
@@ -1236,6 +1237,16 @@ EOF;
 				'css'      => 'width: (3em + (10px * 2))',
 				'expected' => '',
 			),
+			// Gap introduced in 6.1.
+			array(
+				'css'      => 'gap: 10px;column-gap: 5px;row-gap: 20px',
+				'expected' => 'gap: 10px;column-gap: 5px;row-gap: 20px',
+			),
+			// Margin and padding logical properties introduced in 6.1.
+			array(
+				'css'      => 'margin-block-start: 1px;margin-block-end: 2px;margin-inline-start: 3px;margin-inline-end: 4px;padding-block-start: 1px;padding-block-end: 2px;padding-inline-start: 3px;padding-inline-end: 4px',
+				'expected' => 'margin-block-start: 1px;margin-block-end: 2px;margin-inline-start: 3px;margin-inline-end: 4px;padding-block-start: 1px;padding-block-end: 2px;padding-inline-start: 3px;padding-inline-end: 4px',
+			),
 		);
 	}