Allows commenting outside edit mode when seamless editing is disabled. (#5422)

shared/editor/lib/Extension.ts

@@ -41,6 +41,10 @@ export default class Extension {
     return {};
   }
 
+  get allowInReadOnly(): boolean {
+    return false;
+  }
+
   keys(_options: {
     type?: NodeType | MarkType;
     schema: Schema;

shared/editor/lib/ExtensionManager.ts

@@ -205,7 +205,7 @@ export default class ExtensionManager {
           callback: CommandFactory,
           attrs: Record<string, any>
         ) => {
-          if (!view.editable) {
+          if (!view.editable && !extension.allowInReadOnly) {
             return false;
           }
           view.focus();