[🐞] v2 Duplicate q:key Attributes on Sibling Component$ Instances Cause DOM Failures

[devcaeg]

Which component is affected?

Qwik Runtime

Describe the bug

When multiple non-conditionally rendered component$ instances are placed inside a

, each instance receives an identical q:key attribute in the rendered DOM. This duplication leads to various failures, such as buttons becoming unresponsive and hover effects not working.

Reproduction

Missing

Steps to reproduce

• Create a
  container.
• Render several component$ instances as children of the
  (without any conditional rendering).
• Inspect the DOM to observe that all component$ instances have the same q:key attribute.
• Interact with UI elements (e.g., click buttons or hover over elements) and notice that the interactions fail (this happens after the first interaction).

System Info

System:
    OS: macOS 15.3.1
    CPU: (8) arm64 Apple M2
    Memory: 469.25 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    bun: 1.2.3 - /opt/homebrew/bin/bun
  Browsers:
    Chrome: 133.0.6943.127
    Edge: 133.0.3065.82
    Safari: 18.3
 npmPackages:
    @qwik.dev/core: https://pkg.pr.new/QwikDev/qwik/@qwik.dev/core@da11736
    @qwik.dev/router: https://pkg.pr.new/QwikDev/qwik/@qwik.dev/router@da11736
    typescript: 5.7.3 => 5.7.3 
    vite: 6.1.1 => 6.1.1

Additional Information

No response

[JerryWu1234]

#7049
@devcaeg is it same according to this PR ？

[devcaeg]

@JerryWu1234

What I see in my project is that many elements have the same “q:key” I think this is a mistake, maybe I am wrong.

[Varixo]

@devcaeg this is normal behavior for the same components I think, so the problem should be somewhere else. Is it possible to add some reproduction?
I can't reproduce it
https://qwikdev-build-v2.qwik-8nx.pages.dev/playground/#f=Q0o0xubG2BKNDqL2xdMqgXjTObcA6EusSQeiAJhpgArgBmoYAF2BSFbwhko1UJ0eEJem1kJcDGlzIKraaojBcGXa2rV24HIH3jwB6oM2Z2o1adpoAroWVN04FhUlVmoYGmjqpWXm5Gioq2vqAZsBUONtQAGjb6cJ9Q1SMwt3vjG0RGoZkpJvUOJmNNfQItcAAA