Canvas tab not working properly until after reload - seems due to --docs flag.

[petechappell-toast]

Describe the bug

When the --docs flag is added to either start-storybook or build-storybook it results in the following:

• toolbar hidden by default
• switching to canvas tab doesn't work (unless you refresh)
• actions panel not showing on canvas tab by default
• when navigating to subsequent stories, the canvas tab is shown as active but the user still see "docs" mode

Screen.Recording.2022-03-03.at.17.30.24.mov

To Reproduce
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I'm not going to push up a public repo for this because it is so easy to reproduce (with minimal changes)

• run npx sb@next repro
• follow the prompts as per usual
• update the package.json file to add the --docs flag

  "storybook": "start-storybook -p 6006 --docs"
  

• run yarn storybook

System

Environment Info:

  System:
    OS: macOS 12.2.1
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Binaries:
    Node: 12.18.4 - ~/.volta/tools/image/node/12.18.4/bin/node
    Yarn: 3.2.0 - ~/.volta/tools/image/yarn/1.22.10/bin/yarn
    npm: 6.14.6 - ~/.volta/tools/image/node/12.18.4/bin/npm
  Browsers:
    Chrome: 98.0.4758.109
    Firefox: 96.0.2
    Safari: 15.3
  npmPackages:
    @storybook/addon-actions: ^6.5.0-alpha.45 => 6.5.0-alpha.45 
    @storybook/addon-docs: ^6.5.0-alpha.45 => 6.5.0-alpha.45 
    @storybook/addon-essentials: ^6.5.0-alpha.45 => 6.5.0-alpha.45 
    @storybook/addon-interactions: ^6.5.0-alpha.45 => 6.5.0-alpha.45 
    @storybook/addon-links: ^6.5.0-alpha.45 => 6.5.0-alpha.45 
    @storybook/react: ^6.5.0-alpha.45 => 6.5.0-alpha.45 
    @storybook/testing-library: ^0.0.9 => 0.0.9 

Additional context

I wonder if this might be related to (or the cause of) other similar issues... For example: #15283

From the SB docs, it looks like the --docs flag should only set the initial view to "docs". But it seems to be doing more than that.

[petechappell-toast]

If you're experiencing this kind of problem switching between the canvas and doc tabs, a short-term fix is to disable the --docs flag from your build.

[shilman]

We’re cleaning house! Storybook has changed a lot since this issue was created and we don’t know if it’s still valid. Please open a new issue referencing this one if:

• this is still a problem in SB 7.x
• you can provide a consistent reproduction in 7.x (at https://storybook.new/ or per repro docs).