Search and menu scroll broken when using pymdownx.tabbed content

[svenhofstede-zz]

Contribution guidelines

• I've read the contribution guidelines and wholeheartedly agree

I've found a bug and checked that ...

• ... the problem doesn't occur with the mkdocs or readthedocs themes
• ... the problem persists when all overrides are removed, i.e. custom_dir, extra_javascript and extra_css
• ... the documentation does not mention anything about my problem
• ... there are no open or closed issues that are related to my problem

Description

When using pymdownx.tabbed content, an javascript error is thrown after version 8.0.0 onwards

Related issue is #3324 but I'm providing steps to reproduce here.

Expected behaviour

Search should work. Scrolling menu on the left should work

Actual behaviour

• Clicking on search or typing does not result in search results popdown.
• Menu bar on left losing ability to scroll
• Javascript error in console

index.ts:77 Uncaught ReferenceError: Missing element: expected ".tabbed-labels" to be present
    at z (index.ts:77)
    at $o (index.ts:97)
    at index.ts:98
    at Array.map (<anonymous>)
    at Po (index.ts:98)
    at bundle.ts:202
    at Array.map (<anonymous>)
    at bundle.ts:202
    at e._subscribe (defer.ts:53)
    at e._trySubscribe (Observable.ts:244)

Steps to reproduce

mkdocs.yaml

site_name: example
theme:
  name: material
plugins:
  - search
nav:
  - example: example.md
markdown_extensions:
  - pymdownx.tabbed

docs/example.md

=== "Some block one"

    Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod
    tempor incididunt ut labore et dolore magna aliqua.
    
=== "Some other block"

    Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod
    tempor incididunt ut labore et dolore magna aliqua.

✅

docker run --rm -it -p 8000:8000 -v ${PWD}:/docs squidfunk/mkdocs-material:7.3.6

🔴

docker run --rm -it -p 8000:8000 -v ${PWD}:/docs squidfunk/mkdocs-material:8.0.0

Package versions

• Python: Python 3.9.2
• MkDocs: 1.2.3
• Material: 8.0.0

Configuration

site_name: example
theme:
  name: material
plugins:
  - search
nav:
  - example: example.md
markdown_extensions:
  - pymdownx.tabbed

System information

• Operating system: Tested on Mac OS and Windows
• Browser: Tested on Chrome, Safari, Edge

[squidfunk]

Thanks for reporting. Intended behavior, as Material for MkDocs dropped support for the legacy style. When doing major upgrades, it's a good idea to check the upgrade guide 😉