Index: src/wp-includes/blocks/categories.php
===================================================================
--- src/wp-includes/blocks/categories.php	(revision 60660)
+++ src/wp-includes/blocks/categories.php	(working copy)
@@ -50,19 +50,9 @@
 		$show_label     = empty( $attributes['showLabel'] ) ? ' screen-reader-text' : '';
 		$default_label  = $taxonomy->label;
 		$label_text     = ! empty( $attributes['label'] ) ? wp_kses_post( $attributes['label'] ) : $default_label;
-		$wrapper_markup = '<div %1$s><label class="wp-block-categories__label' . $show_label . '" for="' . esc_attr( $id ) . '">' . $label_text . '</label>%2$s</div>';
+		$wrapper_markup = '<div %1$s><form action="' . esc_url( home_url() ) . '" method="get"><label class="wp-block-categories__label' . $show_label . '" for="' . esc_attr( $id ) . '">' . $label_text . '</label>%2$s<button type="submit">' . esc_html__( 'View' ) . '</button></form></div>';
 		$items_markup   = wp_dropdown_categories( $args );
 		$type           = 'dropdown';
-
-		if ( ! is_admin() ) {
-			// Inject the dropdown script immediately after the select dropdown.
-			$items_markup = preg_replace(
-				'#(?<=</select>)#',
-				build_dropdown_script_block_core_categories( $id ),
-				$items_markup,
-				1
-			);
-		}
 	} else {
 		$args['show_option_none'] = $taxonomy->labels->no_terms;
 
Index: src/wp-includes/widgets/class-wp-widget-categories.php
===================================================================
--- src/wp-includes/widgets/class-wp-widget-categories.php	(revision 60660)
+++ src/wp-includes/widgets/class-wp-widget-categories.php	(working copy)
@@ -90,25 +90,9 @@
 			 */
 			wp_dropdown_categories( apply_filters( 'widget_categories_dropdown_args', $cat_args, $instance ) );
 
+			echo '<button type="submit">' . esc_html__( 'View' ) . '</button>';
 			echo '</form>';
 
-			ob_start();
-			?>
-
-<script>
-(function() {
-	var dropdown = document.getElementById( "<?php echo esc_js( $dropdown_id ); ?>" );
-	function onCatChange() {
-		if ( dropdown.options[ dropdown.selectedIndex ].value > 0 ) {
-			dropdown.parentNode.submit();
-		}
-	}
-	dropdown.onchange = onCatChange;
-})();
-</script>
-
-			<?php
-			wp_print_inline_script_tag( wp_remove_surrounding_empty_script_tags( ob_get_clean() ) );
 		} else {
 			$format = current_theme_supports( 'html5', 'navigation-widgets' ) ? 'html5' : 'xhtml';