display-character-count-to-RichTextBlock

client/src/components/StreamField/blocks/FieldBlock.js

@@ -155,6 +155,10 @@ export class FieldBlock {
       attributes.required = '';
     }
 
+    if (this.blockDef.meta.maxLength) {
+      attributes.maxLength = this.blockDef.meta.maxLength;
+    }
+
     return attributes;
   }
 

client/src/entrypoints/admin/telepath/widgets.js

@@ -378,6 +378,11 @@ class DraftailRichTextArea {
     input.id = id;
     input.name = name;
 
+    if (typeof options?.attributes === 'object') {
+      Object.entries(options.attributes).forEach(([key, value]) => {
+        input.setAttribute(key, value);
+      });
+    }
     // If the initialState is an EditorState, rather than serialized rawContentState, it's
     // easier for us to initialize the widget blank and then setState to the correct state
     const initialiseBlank = !!initialState.getCurrentContent;

wagtail/blocks/field_block.py

@@ -120,6 +120,9 @@ class FieldBlockAdapter(Adapter):
         if block.field.help_text:
             meta["helpText"] = block.field.help_text
 
+        if hasattr(block, "max_length") and block.max_length is not None:
+            meta["maxLength"] = block.max_length
+
         return [
             block.name,
             block.field.widget,
@@ -678,6 +681,7 @@ class RichTextBlock(FieldBlock):
             "help_text": help_text,
             "validators": validators,
         }
+        self.max_length = max_length
         self.editor = editor
         self.features = features
         self.search_index = search_index