Merge branch 'master' into fix/use-srcset-for-cover

Conflicts:
	lib/client-assets.php

lib/client-assets.php

@@ -658,6 +658,18 @@ function gutenberg_extend_block_editor_settings_with_default_editor_styles( $set
 }
 add_filter( 'block_editor_settings', 'gutenberg_extend_block_editor_settings_with_default_editor_styles' );
 
+/**
+ * Adds a flag to the editor settings to know whether we're in FSE theme or not.
+ *
+ * @param array $settings Default editor settings.
+ *
+ * @return array Filtered editor settings.
+ */
+function gutenberg_extend_block_editor_settings_with_fse_theme_flag( $settings ) {
+	$settings['isFSETheme'] = gutenberg_is_fse_theme();
+	return $settings;
+}
+add_filter( 'block_editor_settings', 'gutenberg_extend_block_editor_settings_with_fse_theme_flag' );
 
 /**
  * Adds a polyfill for object-fit in environments which do not support it.