revert: Restore conditional the_content filter usage

- Reverted nuclear option from v0.4.8
- get_post_data() now uses the_content filter conditionally
- All other protections remain in place
- Memory leak investigation to be continued later

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -7,6 +7,72 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.4.9] - 2026-02-02
+
+### Changed
+
+- **Reverted nuclear option** - Restored conditional the_content filter usage
+  - `get_post_data()` now uses the_content filter only when NOT in shortcode context, NOT at depth > 1, and NOT loading page template
+  - All other protections remain in place (render depth, page template loading flag, main template lock, shortcode context)
+  - Memory leak investigation to be continued later
+
+## [0.4.8] - 2026-02-02
+
+### Fixed
+
+- **Nuclear option: NEVER apply the_content filter** - Completely removed the_content filter usage (reverted in 0.4.9)
+  - `get_post_data()` now ALWAYS strips shortcodes and uses raw content
+  - NEVER calls `apply_filters('the_content', ...)` or `get_the_excerpt()`
+  - FediStream posts don't need shortcode processing in their content anyway
+  - This guarantees no recursion through WordPress hook system
+
+## [0.4.7] - 2026-02-02
+
+### Fixed
+
+- **Hard main template rendering lock** - Added additional protection at Plugin::render() level
+  - Added `$rendering_main_template` flag that completely blocks any other render calls while main template is rendering
+  - Reduced MAX_RENDER_DEPTH from 5 to 2 (allows one level of {% include %} but prevents deeper recursion)
+  - template-wrapper.php now passes `is_main_template = true` to enable the hard lock
+  - Any render attempt during main template rendering is immediately blocked
+
+## [0.4.6] - 2026-02-02
+
+### Fixed
+
+- **Page template loading lock** - Block ALL shortcode rendering during page template loading
+  - Added `$loading_page_template` flag in TemplateLoader
+  - template-wrapper.php now sets this flag before loading theme header/footer
+  - Shortcodes::render_template() checks this flag and returns early if set
+  - This prevents any recursion triggered by theme components, widgets, or other plugins during page template loading
+  - Main template rendering still works (uses Plugin::render() directly, not through Shortcodes)
+
+## [0.4.5] - 2026-02-02
+
+### Fixed
+
+- **Multi-layer recursion protection** - Added additional safeguards against infinite Twig rendering
+  - Added render depth tracking in `Plugin::render()` with max depth of 5
+  - Strip shortcodes from content when in shortcode context (prevents any later `do_shortcode()` calls from triggering recursion)
+  - This addresses the Twig StagingExtension.php recursion error
+
+## [0.4.4] - 2026-02-02
+
+### Fixed
+
+- **Fix excerpt-triggered recursion** - `get_the_excerpt()` internally calls `the_content` filter when generating auto-excerpts
+  - When in shortcode context, now uses raw `$post->post_excerpt` or generates simple excerpt with `wp_trim_words()` instead
+  - This was the remaining recursion path causing memory exhaustion in `class-wp-hook.php`
+
+## [0.4.3] - 2026-02-02
+
+### Fixed
+
+- **Further memory leak fix** - v0.4.2 fix was still incomplete
+  - Changed `$in_shortcode_context` boolean to `$shortcode_context_depth` counter to properly handle nested shortcodes
+  - Added shortcode context protection to `template-wrapper.php` for single page views
+  - This fixes the remaining recursion path where `the_content` filter was still being applied when viewing single FediStream posts (artists, albums, tracks, playlists)
+
 ## [0.4.2] - 2026-02-02
 
 ### Fixed
@@ -217,7 +283,14 @@ Initial release of WP FediStream - a WordPress plugin for streaming music over A
 
 ---
 
-[Unreleased]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.2...HEAD
+[Unreleased]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.9...HEAD
+[0.4.9]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.8...v0.4.9
+[0.4.8]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.7...v0.4.8
+[0.4.7]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.6...v0.4.7
+[0.4.6]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.5...v0.4.6
+[0.4.5]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.4...v0.4.5
+[0.4.4]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.3...v0.4.4
+[0.4.3]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.2...v0.4.3
 [0.4.2]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.1...v0.4.2
 [0.4.1]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.4.0...v0.4.1
 [0.4.0]: https://src.bundespruefstelle.ch/magdev/wp-fedistream/compare/v0.3.0...v0.4.0

includes/Frontend/Shortcodes.php

@@ -552,6 +552,12 @@ class Shortcodes {
      * @return string
      */
     private function render_template( string $template, array $context ): string {
+        // Block shortcode rendering while loading page template to prevent recursion.
+        // This catches any shortcodes triggered by theme header/footer, widgets, etc.
+        if ( TemplateLoader::is_loading_page_template() ) {
+            return '<!-- FediStream: shortcode blocked during page template loading -->';
+        }
+
         // Check for unlicensed mode.
         if ( $this->unlicensed_mode ) {
             return $this->get_unlicensed_message();

includes/Frontend/TemplateLoader.php

@@ -36,12 +36,49 @@ class TemplateLoader {
     private const MAX_RECURSION_DEPTH = 3;
 
     /**
-     * Whether we're currently in a shortcode rendering context.
-     * When true, the_content filter is skipped to prevent recursive shortcode processing.
+     * Shortcode rendering context depth counter.
+     * When > 0, the_content filter is skipped to prevent recursive shortcode processing.
+     * Using a counter instead of boolean to handle nested shortcodes properly.
+     *
+     * @var int
+     */
+    private static int $shortcode_context_depth = 0;
+
+    /**
+     * Flag indicating we're currently loading a FediStream page template.
+     * This completely blocks any nested FediStream shortcode rendering.
      *
      * @var bool
      */
-    private static bool $in_shortcode_context = false;
+    private static bool $loading_page_template = false;
+
+    /**
+     * Enter page template loading mode.
+     * This blocks ALL shortcode rendering during page template loading.
+     *
+     * @return void
+     */
+    public static function enter_page_template_loading(): void {
+        self::$loading_page_template = true;
+    }
+
+    /**
+     * Exit page template loading mode.
+     *
+     * @return void
+     */
+    public static function exit_page_template_loading(): void {
+        self::$loading_page_template = false;
+    }
+
+    /**
+     * Check if we're loading a page template.
+     *
+     * @return bool
+     */
+    public static function is_loading_page_template(): bool {
+        return self::$loading_page_template;
+    }
 
     /**
      * Enter shortcode rendering context.
@@ -50,7 +87,7 @@ class TemplateLoader {
      * @return void
      */
     public static function enter_shortcode_context(): void {
-        self::$in_shortcode_context = true;
+        ++self::$shortcode_context_depth;
     }
 
     /**
@@ -60,7 +97,9 @@ class TemplateLoader {
      * @return void
      */
     public static function exit_shortcode_context(): void {
-        self::$in_shortcode_context = false;
+        if ( self::$shortcode_context_depth > 0 ) {
+            --self::$shortcode_context_depth;
+        }
     }
 
     /**
@@ -69,7 +108,7 @@ class TemplateLoader {
      * @return bool
      */
     public static function is_in_shortcode_context(): bool {
-        return self::$in_shortcode_context;
+        return self::$shortcode_context_depth > 0;
     }
 
     /**
@@ -253,13 +292,37 @@ class TemplateLoader {
         // Skip the_content filter if:
         // 1. We're in a shortcode context (prevents recursive shortcode processing)
         // 2. We're at depth > 1 (nested data loading)
-        $skip_content_filter = self::$in_shortcode_context || self::$recursion_depth > 1;
+        // 3. We're loading a page template
+        $skip_content_filter = self::$shortcode_context_depth > 0
+            || self::$recursion_depth > 1
+            || self::$loading_page_template;
+
+        // When skipping content filter, use raw excerpt to avoid get_the_excerpt()
+        // triggering the_content filter internally when generating auto-excerpts.
+        if ( $skip_content_filter ) {
+            $excerpt = $post->post_excerpt;
+            if ( empty( $excerpt ) ) {
+                // Generate a simple excerpt without triggering the_content filter.
+                $excerpt = wp_trim_words( wp_strip_all_tags( $post->post_content ), 55, '…' );
+            }
+        } else {
+            $excerpt = get_the_excerpt( $post );
+        }
+
+        // When skipping content filter, strip shortcodes to prevent them from
+        // being processed by anything else that might call do_shortcode on the output.
+        if ( $skip_content_filter ) {
+            $content = strip_shortcodes( $post->post_content );
+            $content = wp_kses_post( $content );
+        } else {
+            $content = apply_filters( 'the_content', $post->post_content );
+        }
 
         $data = array(
             'id'        => $post->ID,
             'title'     => get_the_title( $post ),
-            'content'   => $skip_content_filter ? wp_kses_post( $post->post_content ) : apply_filters( 'the_content', $post->post_content ),
-            'excerpt'   => get_the_excerpt( $post ),
+            'content'   => $content,
+            'excerpt'   => $excerpt,
             'permalink' => get_permalink( $post ),
             'thumbnail' => get_the_post_thumbnail_url( $post->ID, 'large' ),
             'date'      => get_the_date( '', $post ),

includes/Frontend/template-wrapper.php

@@ -13,6 +13,12 @@ if ( ! defined( 'ABSPATH' ) ) {
 use WP_FediStream\Plugin;
 use WP_FediStream\Frontend\TemplateLoader;
 
+// Enter page template loading mode - this completely blocks nested FediStream rendering.
+TemplateLoader::enter_page_template_loading();
+
+// Also enter shortcode context to prevent recursive shortcode processing in post content.
+TemplateLoader::enter_shortcode_context();
+
 // Get template context.
 $context = TemplateLoader::get_context();
 
@@ -54,7 +60,8 @@ get_header();
     if ( $template_name ) {
         try {
             // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
-            echo $plugin->render( $template_name, $context );
+            // Pass true for is_main_template to set the hard rendering lock.
+            echo $plugin->render( $template_name, $context, true );
         } catch ( \Exception $e ) {
             if ( WP_DEBUG ) {
                 echo '<div class="fedistream-error">';
@@ -75,4 +82,8 @@ get_header();
 </main>
 
 <?php
+// Exit shortcode context and page template loading mode.
+TemplateLoader::exit_shortcode_context();
+TemplateLoader::exit_page_template_loading();
+
 get_footer();

includes/Plugin.php

@@ -55,6 +55,29 @@ final class Plugin {
      */
     private ?\Twig\Environment $twig = null;
 
+    /**
+     * Current Twig render depth to prevent infinite recursion.
+     *
+     * @var int
+     */
+    private static int $render_depth = 0;
+
+    /**
+     * Maximum allowed Twig render depth.
+     * Set to 2 to allow one level of nested includes but prevent deeper recursion.
+     *
+     * @var int
+     */
+    private const MAX_RENDER_DEPTH = 2;
+
+    /**
+     * Flag to track if we're currently rendering the main page template.
+     * This is a hard lock that prevents ANY other rendering.
+     *
+     * @var bool
+     */
+    private static bool $rendering_main_template = false;
+
     /**
      * Post type instances.
      *
@@ -842,8 +865,35 @@ final class Plugin {
      * @param array  $context  Template context variables.
      * @return string Rendered template.
      */
-    public function render( string $template, array $context = array() ): string {
-        return $this->twig->render( $template . '.twig', $context );
+    public function render( string $template, array $context = array(), bool $is_main_template = false ): string {
+        // If we're already rendering the main template, block any other renders.
+        if ( self::$rendering_main_template && ! $is_main_template ) {
+            return '<!-- FediStream: blocked during main template render -->';
+        }
+
+        // Prevent infinite recursion in Twig rendering.
+        if ( self::$render_depth >= self::MAX_RENDER_DEPTH ) {
+            return '<!-- FediStream: render depth exceeded -->';
+        }
+
+        // Set main template lock if this is the main template.
+        $was_main = self::$rendering_main_template;
+        if ( $is_main_template ) {
+            self::$rendering_main_template = true;
+        }
+
+        ++self::$render_depth;
+
+        try {
+            $result = $this->twig->render( $template . '.twig', $context );
+        } finally {
+            --self::$render_depth;
+            if ( $is_main_template ) {
+                self::$rendering_main_template = $was_main;
+            }
+        }
+
+        return $result;
     }
 
     /**

wp-fedistream.php

@@ -3,7 +3,7 @@
  * Plugin Name: WP FediStream
  * Plugin URI: https://src.bundespruefstelle.ch/magdev/wp-fedistream
  * Description: Stream music over ActivityPub - Build your own music streaming platform for Musicians and Labels.
- * Version: 0.4.2
+ * Version: 0.4.9
  * Requires at least: 6.4
  * Requires PHP: 8.3
  * Author: Marco Graetsch
@@ -26,7 +26,7 @@ if ( ! defined( 'ABSPATH' ) ) {
  *
  * @var string
  */
-define( 'WP_FEDISTREAM_VERSION', '0.4.2' );
+define( 'WP_FEDISTREAM_VERSION', '0.4.9' );
 
 /**
  * Plugin file path.