‼️ 🛑 Composition is broken in Safari (desktop and mobile)

[tim-mukhin]

Hi!
Could you please fix this issue. It's blocker for us. Most of our developers in company use Macbooks and many of them use Safari.

Describe the bug
The Composition on Safari browser (desktop and mobile) is broken. See the reproducing steps.

To Reproduce

1. First option with official storybook
   Steps:

• Open official storybook from the docs.
• Scroll down on the left panel to external storybook, open any story, wait until it loads and select the Docs tab

• Scroll stories back to top and choose any story from the current storybook
• Now the docs tab will stuck with docs from external storybook

2. Second option with repro repository

• Clone this repo
• Install dependencies
• Start storybook with yarn storybook
• Scroll down on the left panel to external storybook sample2, open any story, wait until it loads and select the Docs tab

• Scroll stories back to top and choose any story from the current storybook
• Now you can see "No docs" block on any docs page

• And after that you can also reproduce the issue from first oprion if you open external 'Official storybook'

System

System:
    OS: macOS 11.5
    CPU: (8) arm64 Apple M1
  Binaries:
    Node: 14.17.4 - ~/.nvm/versions/node/v14.17.4/bin/node
    Yarn: 3.0.1 - ~/.nvm/versions/node/v14.17.4/bin/yarn
    npm: 6.14.14 - ~/.nvm/versions/node/v14.17.4/bin/npm
  Browsers:
    Edge: 92.0.902.78
    Firefox: 90.0.2
    Safari: 14.1.2
  npmPackages:
    @storybook/addon-actions: ^6.4.0-alpha.32 => 6.4.0-alpha.32 
    @storybook/addon-docs: ^6.4.0-alpha.32 => 6.4.0-alpha.32 
    @storybook/addon-essentials: ^6.4.0-alpha.32 => 6.4.0-alpha.32 
    @storybook/addon-links: ^6.4.0-alpha.32 => 6.4.0-alpha.32 
    @storybook/node-logger: ^6.4.0-alpha.32 => 6.4.0-alpha.32 
    @storybook/preset-create-react-app: ^3.2.0 => 3.2.0 
    @storybook/react: ^6.4.0-alpha.32 => 6.4.0-alpha.32 

Additional context
The issue also reprodusable on MacOS Catalina and iOS 14

[tim-mukhin]

@shilman

Hi!
Could you please consider this issue 🙏
It's a blocker for us

[shilman]

@tim-mukhin we're looking at composition again as part of a giant performance refactor that's happening in 6.4, so I'll try to squeeze this in.

[shilman]

Boo-yah!! I just released https://github.com/storybookjs/storybook/releases/tag/v6.5.0-alpha.49 containing PR #17679 that references this issue. Upgrade today to the @next NPM tag to try it out!

npx sb upgrade --prerelease

Closing this issue. Please re-open if you think there's still more to do.

[shilman]

Crikey!! I just released https://github.com/storybookjs/storybook/releases/tag/v6.4.20 containing PR #17679 that references this issue. Upgrade today to the @latest NPM tag to try it out!

npx sb upgrade

[tim-mukhin]

Yay! Many thanks! Already upgrading and testing 🥳🥳🥳