fix: image replacement on admin ajax requests

inc/app_replacer.php

@@ -164,7 +164,9 @@ public function init() {
 	 * @return bool If we can replace the image.
 	 */
 	public function should_replace() {
-
+		if ( Optml_Manager::is_ajax_request() ) {
+			return true;
+		}
 		if ( is_admin() || ! $this->settings->is_connected() || ! $this->settings->is_enabled() || is_customize_preview() ) {
 			return false; // @codeCoverageIgnore
 		}

inc/manager.php

@@ -45,7 +45,7 @@ public function init() {
 		 * Otherwise, we can hook first to avoid any other plugins to take care of replacement.
 		 */
 		add_action(
-			'template_redirect',
+			self::is_ajax_request() ? 'init' : 'template_redirect',
 			array(
 				$this,
 				'process_template_redirect_content',
@@ -55,6 +55,31 @@ public function init() {
 		add_action( 'get_post_metadata', array( $this, 'replace_meta' ), PHP_INT_MAX, 4 );
 	}
 
+	/**
+	 * Check if we are in a ajax contex where we should enable replacement.
+	 *
+	 * @return bool Is ajax request?
+	 */
+	public static function is_ajax_request() {
+
+		if ( ! function_exists( 'is_user_logged_in' ) ) {
+			return false;
+		}
+		// Disable for logged in users to avoid unexpected results.
+		if ( is_user_logged_in() ) {
+			return false;
+		}
+
+		if ( ! function_exists( 'wp_doing_ajax' ) ) {
+			return false;
+		}
+		if ( ! wp_doing_ajax() ) {
+			return false;
+		}
+
+		return true;
+	}
+
 	/**
 	 * Handles the url replacement in options and theme mods.
 	 */