Added missing isToolshown documentation

- MIGRATION.md
- Options Parameters documentation

MIGRATION.md

@@ -196,6 +196,7 @@ addParameters({
     }),
     isFullscreen: false,
     panelPosition: 'right',
+    isToolshown: true,
   },
 });
 ```
@@ -211,9 +212,12 @@ Here is the mapping from old options to new:
 | showAddonPanel    | showPanel        |
 | addonPanelInRight | panelPosition    |
 | showSearchBox     |                  |
+|                   | isToolshown      |
 
 Storybook v5 removes the search dialog box in favor of a quick search in the navigation view, so `showSearchBox` has been removed.
 
+Storybook v5 introduce a new tool bar above the story view and you can show\hide it with the new `isToolshown` option. 
+
 ## Individual story decorators
 
 The behavior of adding decorators to a kind has changed in SB5 ([#5781](https://github.com/storybooks/storybook/issues/5781)).

docs/src/pages/configurations/options-parameter/index.md

@@ -70,6 +70,11 @@ addParameters({
      * @type {Boolean}
      */
     enableShortcuts: true,
+    /**
+     * show/hide tool bar
+     * @type {Boolean}
+     */
+    isToolshown: true,
     /**
      * theme storybook, see link below
      */