Sidebar navigation does not work in production (6.0.0-rc.5 + addon-docs)

[koop-stripe]

Describe the bug
Sidebar navigation does not work when building addon-docs for production.

To Reproduce
Steps to reproduce the behavior:

1. Build storybook for production build-storybook --docs -c .storybook -o .storybook-dist
2. Start the server, load a page in your browser.
3. Try to navigate to another page by clicking a page title in the sidebar.

Expected behavior
The browser URL changes and storybook navigates to the new page.

Actual behavior
The browser URL changes but the preview doesn’t change.

System:

System:
OS: macOS 10.15.4
CPU: (8) x64 Intel(R) Core(TM) i7-7920HQ CPU @ 3.10GHz
Binaries:
Node: 10.16.0 - ~/.nodenv/versions/10.16.0/bin/node
Yarn: 1.19.1 - ~/.yarn/bin/yarn
npm: 6.9.0 - ~/.nodenv/versions/10.16.0/bin/npm
Browsers:
Chrome: 83.0.4103.116
Firefox: 78.0.1
Safari: 13.1
npmPackages:
@storybook/addon-docs: 6.0.0-rc.5 => 6.0.0-rc.5
@storybook/react: 6.0.0-rc.5 => 6.0.0-rc.5

[shilman]

Looks like a regression due to #11537. @ndelangen can you investigate?

[ndelangen]

I'm investigating!

[ndelangen]

I'm trying to reproduce, but I'm unable to. The navigation seems to work for me, in both dev & prod mode.

Could you make me a reproduction repo?

[blaine-stripe]

@ndelangen This was happening on rc.5 but I upgraded to rc.13 and I can't reproduce. Where you checking rc.5? Anyway, might have been fixed in between!

[blaine-stripe]

Edit: The issue below seems to be related to another issue (#10846)

Doing some more digging here, so might continue to update with some information:

When I navigate, an error is thrown in my console that says

TypeError: Cannot read property 'toLowerCase' of null
    at sanitize (index.js:66)
    at sanitizeSafe (index.js:73)
    at toId (index.js:87)

It looks like null values are being passed to the sanitize method through toId

[shilman]

Thanks @blaine-stripe. Closing this & will follow up on the other issue.