detachedcallback should be disconnectedcallback

[filipbech]

I might be totally off here, but if I understand the source correctly you are listening for the old v0 callback that the browser nolonger fires - so cleanup wont happen.

https://developer.mozilla.org/en-US/docs/Web/Web_Components/Using_custom_elements#Using_the_lifecycle_callbacks

This might be something specific to preact (where Im no expert), in which case you can just close this issue.

Would you like me to do a PR for this change?

[marvinhagemeister]

Good catch! That is indeed a bug and it should be changer to disconnectedCallback. Would love a PR for this 👍

[marvinhagemeister]

Fixed by #38