[Bug]: layout.showPanel is in the docs, but doesn't work

[syabro]

Describe the bug

in types AddonConfig doesn't have it

interface Addon_Config {
    theme?: ThemeVars;
    layout?: {
        showSidebar?: API_LayoutCustomisations['showSidebar'];
        showToolbar?: API_LayoutCustomisations['showToolbar'];
    };
    toolbar?: {
        [id: string]: Addon_ToolbarConfig;
    };
    sidebar?: API_SidebarOptions;
    [key: string]: any;
}

Reproduction link

no

Reproduction steps

Create empty project with manager.ts code

import { addons } from 'storybook/manager-api';

addons.setConfig({
  layout: {
    showPanel: false
  }
});

System

Storybook Environment Info:

  System:
    OS: macOS 15.5
    CPU: (12) arm64 Apple M2 Max
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 21.6.2 - ~/.nvm/versions/node/v21.6.2/bin/node
    Yarn: 1.22.22 - /opt/homebrew/bin/yarn
    npm: 10.2.4 - ~/.nvm/versions/node/v21.6.2/bin/npm
    pnpm: 9.4.0 - ~/.nvm/versions/node/v21.6.2/bin/pnpm <----- active
  npmPackages:
    @storybook/addon-links: ^9.0.17 => 9.0.17
    @storybook/builder-vite: ^9.0.17 => 9.0.17
    @storybook/react-vite: ^9.0.17 => 9.0.17
    storybook: ^9.0.17 => 9.0.17

Additional context

No response

[dosubot]

Hi @syabro! I'm Dosu and I’m helping the storybook team.

You're right—while the docs list layout.showPanel as a config option, it's not actually supported in Storybook 9.x. The type definitions and implementation only support showSidebar and showToolbar under layout, and setting showPanel in addons.setConfig has no effect. Panel visibility is managed internally by state, not by config, so this is a documentation bug, not a feature regression or removal. If you need to hide the panel, you'll need to do it manually in the UI or via keyboard shortcuts; there's no config-based workaround at this time.
Reference: Storybook UI config docs, Addon_Config type.

To reply, just mention @dosu.

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[syabro]

@dosu I want to hide it automatically

[dosubot]

There's no config option to hide the panel automatically, but you can do it programmatically in your .storybook/manager.ts by registering a manager-side addon and calling api.togglePanel(false) after the stories are loaded. Example:

import { addons } from '@storybook/manager-api';

addons.register('hide-panel', (api) => {
  api.once('storySpecified', () => {
    api.togglePanel(false);
  });
});

This hides the panel for the current session each time Storybook loads. If you want it to always be hidden, this code needs to run on every load. See how similar logic is used in official addons like onboarding for reference
(source, API docs).

To reply, just mention @dosu.

---

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[syabro]

@dosu you provide broken code
it must be

import { addons } from 'storybook/manager-api';

but overall works

[dosubot]

Thanks for catching that! You're right—the correct import for Storybook 9.x is import { addons } from 'storybook/manager-api';. Glad the workaround works for you. If you run into anything else or need more tweaks, let me know!

To reply, just mention @dosu.

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[syabro]

@dosu why showPanel was removed?

[dosubot]

'showPanel' was never actually a supported config option in Storybook 9.x—its mention in the docs is a documentation bug, not a removed feature. Panel visibility is managed internally by UI state and can only be controlled programmatically (for example, with api.togglePanel(false) in a manager-side addon), not via static config. There's no official replacement config; the recommended approach is to use the API in your manager code if you want to hide the panel automatically. Reference

To reply, just mention @dosu.

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