Update placeholder recipe

Author: texnixe

content/docs/2_cookbook/7_extensions/0_use-placeholders/cookbook-recipe.txt

@@ -10,7 +10,6 @@ Placeholders are a powerful way to include repeatedly used text snippets like co
 
 By default, such placeholders are wrapped in double curly braces like this:
 
-
 ```kirbytext
 Text:
 
@@ -57,7 +56,7 @@ With this in place, we can pass this array to the `Str::template()` method:
 
 
 ```php
-<?= Str::template($page->text()->kt(), option('placeholders', [])) ?>
+<?= Str::template($page->text()->kt(), option('placeholders')) ?>
 ```
 
 Now, if we want to add additional placeholders, we can do that in the config.
@@ -68,7 +67,7 @@ But hey, this is still quite limited.
 
 Maybe your editors would prefer to have control over the types of placeholders they need and what they should be replaced with. A structure field lends itself well to this purpose, and the `site.yml` blueprint is a good place to define site-wide placeholders.
 
-```yaml
+```yaml "/site/blueprints/site.yml"
 placeholders:
   label: Text replacements
   type: structure
@@ -85,7 +84,7 @@ placeholders:
         The replacement text is the text that will replace your keyholders.
 ```
 
-To get the array of options from this field, we create a `toOptions()` (link: docs/reference/plugins/extensions/field-methods text: field method) in a plugin:
+To get an array of options from this field, we create a `toOptions()` (link: docs/reference/plugins/extensions/field-methods text: field method) in a plugin:
 
 ```php "/site/plugins/placeholders/index.php"
 
@@ -147,8 +146,6 @@ Kirby::plugin('cookbook/placeholders', [
 ]);
 ```
 
-
-
 ## Wrapping the replacement code in a hook
 
 We can automate it even more, though. A hook replaces all the placeholders automatically, so that we don't even have to call our method in templates anymore:
@@ -166,6 +163,27 @@ Kirby::plugin('cookbook/placeholders', [
 ]);
 ```
 
+For cases that don't use `kirbytext()` (layout field, blocks field, writer field etc-), you can apply a `page.render:after` hook instead that replaces your placeholders all over your site in the rendered HTML, independent of the type of field where the placeholder is used:
+
+```php "/site/plugins/placeholders/index.php"
+<?php
+
+Kirby::plugin('cookbook/placeholders', [
+    'hooks' => [
+        'page.render:after' => function (string $contentType, string $html) {
+            if ($contentType !== 'html') {
+                return $html;
+            }
+
+            return Str::template($html, site()->placeholders()->toOptions());
+
+        },
+    ]
+]);
+```
+
+The `replace()` field method is no longer needed when we use this hook.
+
 ## The final plugin
 
 For the final plugin, we want to get rid of some of the hardcoded stuff and leave it to the developer to decide where the replacements are defined, in the config or by the editor in a structure field, or even allow overriding/extending the replacements defined in `config.php`.
@@ -201,6 +219,7 @@ Kirby::plugin('cookbook/placeholders', [
             return $result;
         }
     ],
+    // Don't use both hooks but only one as required, remove or comment the one you don't need
     'hooks' => [
         'kirbytags:before' => function ($text) {
 
@@ -218,7 +237,14 @@ Kirby::plugin('cookbook/placeholders', [
             $options = array_merge($defaults, $options);
 
             return Str::template($text, $options);
-        }
+        },
+       'page.render:after' => function (string $contentType, string $html) {
+            if ($contentType !== 'html') {
+                return $html;
+            }
+
+            return Str::template($html, site()->placeholders()->toOptions());
+        },
     ]
 ]);
 ```