[bugfix] image defaults, progressive JPEG, session reopen, debugger on redirects

Four fixes plus a changelog consolidation.

#4282 - `images.defaults` was gated on `method_exists()` since 2.0.22, but
image manipulations are dispatched by `ImageMediaTrait::__call()` rather than
being real methods, so `resize`, `crop`, `rotate` and every other processing
default was silently dropped. Check the magic-action allowlist too. Separately,
`link()` swept the image's own HTML attributes onto the anchor as `data-*` and
`Link` then reset them off the image, so `loading: lazy` in the defaults became
`data-loading` on the `<a>`. Attributes now follow the image they describe;
only width/height are still mirrored onto the anchor for lightbox scripts.

#4284 - `unset($this->image)` removed the declared property, so every later
write fell through to `Data::__set()` and landed in `$items['image']`,
overwriting the media type's own settings. That has disabled every
`media.yaml` per-type default filter since 1.4.6, progressive JPEG among them.
Assign null instead, and promote progressive JPEG to a real
`system.images.progressive_jpeg` option applied to JPEG output only - the old
blanket filter would also have interlaced every resized PNG.

#4281 - `reopen()` re-read the session from storage without keeping what the
request had already done, so a write made before the reopen was reverted.
Capture and merge, bail out if the session was destroyed underneath us, and
drop the `use_only_cookies` option that does nothing and is deprecated on 8.4.
`close()` now reopens so an in-place change nothing announced still commits.

#4280 - `render()` asked for `$grav['page']` before checking there was a bar to
draw, so a response that returned early from `InitializeProcessor` resolved a
page from scratch that late and fell over on Login's `user` service.

Author: rhukster

CHANGELOG.md

@@ -3,17 +3,19 @@
 
 1. [](#new)
     * **A dependency can now name the generation of Grav it is for.** A plugin that supports both 1.7 and 2.0 often needs a different version of the same dependency on each, so a `dependencies` entry takes an optional `grav` key: `- { name: form, version: '>=9.1.0', grav: '2.0' }`. Entries without it apply everywhere, so existing blueprints are unchanged. See [Plugin Compatibility](https://learn.getgrav.org/20/plugins/plugin-compatibility#requiring-different-versions-per-grav-generation)
+    * A new `system.images.progressive_jpeg` setting, on by default, controls whether resized and cached JPEGs are saved as progressive
 
 1. [](#bugfix)
     * Installing a package whose dependency is not in the GPM index now says so and carries on, instead of stopping the command with a PHP fatal error. A plugin that still asks for the Grav 1.7 admin plugin was enough to trigger it [getgrav/grav-premium-issues#618](https://github.com/getgrav/grav-premium-issues/issues/618)
     * A plugin that asks for the `admin` plugin now has that read as Admin 2 on Grav 2, so a plugin written for both 1.7 and 2.0 installs instead of failing on a dependency that cannot exist there. The version it asks for is not carried over, because it describes the old admin's numbering [getgrav/grav-premium-issues#618](https://github.com/getgrav/grav-premium-issues/issues/618)
     * Any other dependency that cannot be installed on this generation of Grav is now left out of the install rather than attempted and failed
-
-# v2.0.24
-## 09/03/2026
-
-1. [](#bugfix)
     * A JSON request whose body is a bare scalar (`"text"`, `12345`, `true`) sent with `Content-Type: application/json` no longer answers a 500 from the request pipeline before any route runs. It is treated as an empty body, so a plugin's webhook or API route gets to answer it, log it and refuse it itself. With `errors.display` on, the old failure also printed a stack trace with server paths to whoever sent it
+    * An image default such as `resize` set in `system.images.defaults` works again. Every image manipulation was being skipped since 2.0.22, leaving only the loading and decoding hints [#4282](https://github.com/getgrav/grav/issues/4282)
+    * Settings such as `loading: lazy` now stay on the image when `link` is also on, instead of moving onto the surrounding link where the browser never sees them [#4282](https://github.com/getgrav/grav/issues/4282)
+    * Resized and cached JPEGs are saved as progressive again, so a photo appears as a whole blurry image that sharpens instead of filling in one line at a time. It has been Grav's default since 2014 but silently stopped working in 1.4.6 [#4284](https://github.com/getgrav/grav/issues/4284)
+    * A media file's own settings from `media.yaml` are no longer overwritten the moment the image is opened, so custom default filters for an image type work again
+    * A URL typed with a trailing slash no longer errors out on a site that has the debugger switched on and the Login plugin protecting page media, because the debug bar is now skipped on redirects, where there is no page to put it on [#4280](https://github.com/getgrav/grav/issues/4280)
+    * With the optional `system.session.read_and_close` setting turned on, a change made to the session early in a request is no longer thrown away by a later write in that same request, and a message added just before a redirect now reaches the page it was meant for [#4281](https://github.com/getgrav/grav/issues/4281)
 
 # v2.0.23
 ## 09/02/2026

system/blueprints/config/system.yaml

@@ -1393,6 +1393,17 @@ form:
                 min: 1
                 max: 100
 
+            images.progressive_jpeg:
+              type: toggle
+              label: PLUGIN_ADMIN.IMAGES_PROGRESSIVE_JPEG
+              help: PLUGIN_ADMIN.IMAGES_PROGRESSIVE_JPEG_HELP
+              highlight: 1
+              options:
+                1: PLUGIN_ADMIN.YES
+                0: PLUGIN_ADMIN.NO
+              validate:
+                type: bool
+
             images.cache_all:
               type: toggle
               label: PLUGIN_ADMIN.CACHE_ALL

system/config/media.yaml

@@ -1,12 +1,12 @@
+# Progressive JPEG is no longer set here: it applied to every image type, and GD's
+# interlace flag also makes PNGs Adam7-interlaced (bigger, slower). It is now
+# `system.images.progressive_jpeg`, applied to JPEG output only. The
+# `image.filters.default` hook below is still honoured for per-type filters.
 types:
   defaults:
     type: file
     thumb: media/thumb.png
     mime: application/octet-stream
-    image:
-      filters:
-        default:
-          - enableProgressive
 
   jpg:
     type: image

system/config/system.yaml

@@ -186,6 +186,7 @@ debugger:
 images:
   adapter: gd                                    # Image adapter to use: gd | imagick
   default_image_quality: 85                      # Default image quality to use when resampling images (85%)
+  progressive_jpeg: true                         # Save resized and cached JPEGs as progressive, so they appear whole and sharpen rather than filling in a line at a time
   cache_all: false                               # Cache all image by default
   cache_perms: '0755'                            # MUST BE IN QUOTES!! Default cache folder perms. Usually '0755' or '0775'
   debug: false                                   # Show an overlay over images indicating the pixel depth of the image when working with retina for example

system/src/Grav/Common/Debugger.php

@@ -715,9 +715,21 @@ public function getCollector($name)
     public function render()
     {
         if ($this->enabled && $this->debugbar) {
-            // Only add assets if Page is HTML
+            // The bar is HTML injected into the response body, and the renderer that
+            // produces it only exists once addAssets() has run -- so there is nothing
+            // to inject on a response that never got that far. Test for that before
+            // asking for `page`: a request that returns early from InitializeProcessor
+            // (the trailing slash redirect, for one) never resolved a page, and
+            // resolving one here would build the pages index and run the
+            // onPageFallBackUrl hooks this late, against plugin services that
+            // onPluginsInitialized never got to register -- Login's `user` among them.
+            if (!$this->renderer || !$this->grav->initialized('page')) {
+                return $this;
+            }
+
+            // Only render the bar if the page is HTML.
             $page = $this->grav['page'];
-            if (!$this->renderer || $page->templateFormat() !== 'html') {
+            if ($page->templateFormat() !== 'html') {
                 return $this;
             }
 

system/src/Grav/Common/Media/Interfaces/MediaObjectInterface.php

@@ -125,6 +125,13 @@ public function parsedownElement($title = null, $alt = null, $class = null, $id
      */
     public function reset();
 
+    /**
+     * Get the HTML attributes set on this medium.
+     *
+     * @return array
+     */
+    public function getAttributes();
+
     /**
      * Add custom attribute to medium.
      *

system/src/Grav/Common/Media/Traits/ImageMediaTrait.php

@@ -19,6 +19,7 @@
 use function extension_loaded;
 use function func_num_args;
 use function function_exists;
+use function in_array;
 
 /**
  * Trait ImageMediaTrait
@@ -53,6 +54,9 @@ trait ImageMediaTrait
     /** @var bool */
     protected $watermark;
 
+    /** @var bool */
+    protected $progressive;
+
     /** @var array */
     public static $magic_actions = [
         'resize', 'forceResize', 'cropResize', 'crop', 'zoomCrop',
@@ -353,8 +357,12 @@ protected function image()
         // Use existing cache folder or if it doesn't exist, create it.
         $cacheDir = $locator->findResource('cache://images', true) ?: $locator->findResource('cache://images', true, true);
 
-        // Make sure we free previous image.
-        unset($this->image);
+        // Make sure we free previous image. Assign null rather than unset(): unset()
+        // removes the declared property, and every later write then falls through to
+        // Data's __set() and lands in $items['image'], overwriting the media type's
+        // own `image` settings with the ImageFile object. That is what silently
+        // killed the default filters in 1.4.6. getgrav/grav#4284.
+        $this->image = null;
 
         /** @var MediaCollectionInterface $media */
         $media = $this->get('media');
@@ -382,6 +390,7 @@ protected function image()
         $this->retina_scale = $config->get('system.images.cls.retina_scale', 1);
 
         $this->watermark = $config->get('system.images.watermark.watermark_all', false);
+        $this->progressive = $config->get('system.images.progressive_jpeg', true);
 
         return $this;
     }
@@ -423,6 +432,14 @@ protected function saveImage()
             $this->watermark();
         }
 
+        // Queued last on purpose: GD keeps the interlace flag on the image resource,
+        // and any operation that builds a new resource (a resize) drops it. Checked
+        // against the resolved output format so a JPEG converted to PNG or WebP is
+        // not interlaced along with it. getgrav/grav#4284.
+        if ($this->progressive && in_array($this->format, ['jpg', 'jpeg'], true)) {
+            $this->image->enableProgressive();
+        }
+
         return $this->image->cacheFile($this->format, $this->quality, false, [$this->get('width'), $this->get('height'), $this->get('modified')]);
     }
 }

system/src/Grav/Common/Media/Traits/MediaObjectTrait.php

@@ -342,6 +342,16 @@ public function parsedownElement($title = null, $alt = null, $class = null, $id
         return $element;
     }
 
+    /**
+     * Get the HTML attributes set on this medium.
+     *
+     * @return array
+     */
+    public function getAttributes()
+    {
+        return $this->attributes;
+    }
+
     /**
      * Reset medium.
      *
@@ -480,8 +490,13 @@ public function link($reset = true, array $attributes = [])
             $this->display('source');
         }
 
-        foreach ($this->attributes as $key => $value) {
-            empty($attributes['data-' . $key]) && $attributes['data-' . $key] = $value;
+        // The image's own HTML attributes stay on the image; Link re-applies them to
+        // the medium it wraps. Only the dimensions are also mirrored onto the anchor,
+        // which is what lightbox scripts read. getgrav/grav#4282.
+        foreach (['width', 'height'] as $key) {
+            if (isset($this->attributes[$key])) {
+                empty($attributes['data-' . $key]) && $attributes['data-' . $key] = $this->attributes[$key];
+            }
         }
 
         empty($attributes['href']) && $attributes['href'] = $this->url();

system/src/Grav/Common/Page/Markdown/Excerpts.php

@@ -304,8 +304,14 @@ static function ($carry, $item) {
         // would leak those the same way. getgrav/grav#4264.
         $defaults = $this->config['images']['defaults'] ?? [];
         if (count($defaults) && $medium instanceof ImageMediaInterface) {
+            // An image manipulation such as `resize` is not a real method, it is
+            // dispatched by ImageMediaTrait::__call() off its own allowlist, so ask
+            // for that too. Without it every processing default was silently dropped.
+            // getgrav/grav#4282.
+            $magic = property_exists($medium, 'magic_actions') ? (array) $medium::$magic_actions : [];
+
             foreach ($defaults as $method => $params) {
-                if (!method_exists($medium, (string) $method)) {
+                if (!method_exists($medium, (string) $method) && !in_array((string) $method, $magic, true)) {
                     continue;
                 }
 

system/src/Grav/Common/Page/Medium/ImageMedium.php

@@ -96,7 +96,7 @@ public function getMeta(): array
     #[\ReturnTypeWillChange]
     public function __destruct()
     {
-        unset($this->image);
+        $this->image = null;
     }
 
     /**