Duplicate story preview in doc panel with svelte

[j3rem1e]

Describe the bug

Framework Svelte.
Randomly, when using Controls in the doc panel, the story is duplicated in the preview panel. Sometimes, the story is not rendered, or rendered on the wrong canvas.

To Reproduce

1. Open the svelte kitchen sink
2. Open the Button Story
3. Click on the rounded control severals times. (It happens more frequently if the change are done fast..)
4. In the preview panel, the story appears twice

Cause
The HOC component doesn't destroy the child component.

[shilman]

Yo-ho-ho!! I just released https://github.com/storybookjs/storybook/releases/tag/v6.2.0-alpha.18 containing PR #13663 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]

Son of a gun!! I just released https://github.com/storybookjs/storybook/releases/tag/v6.1.15 containing PR #13663 that references this issue. Upgrade today to the @latest NPM tag to try it out!

npx sb upgrade