Signals don't work

[alexamy]

• [x] Check if updating to the latest Preact version resolves the issue

Describe the bug When using latest Preact version (v10.12.1), signals aren't working.

To Reproduce I'm using static html page without bundler.

• Broken: Preact v10.12.1 + signal: https://codesandbox.io/s/preact-signal-bug-s91cfu
• Broken: Preact v10.12.1 + useSignal: https://codesandbox.io/s/preact-usesignal-bug-0c2x6q

Steps to reproduce the behavior:

1. Open sandbox
2. Click '+' button

Expected behavior The count incrementing by 1 after '+' button press.

Actual behavior In case of signal the count stays at 0 after '+' button press. In case of useSignal page isn't rendered at all.

Solution Downgrade to Preact v10.11.3.

• Works: Preact v10.11.3 + signal: https://codesandbox.io/s/preact-signal-bug-old-preact-s5teou
• Works: Preact v10.11.3 + useSignal: https://codesandbox.io/s/preact-usesignal-bug-old-preact-kpnfmr

[alexamy]

First issue was opened in https://github.com/preactjs/signals/issues/303.

[marvinhagemeister]

Quoting the other issue:

This is neither an issue with Preact or with signals. The code is not updating because you're loading multiple copies of Preact in that sandbox which are not aware of each other. Hooks require singletons to work behind the scenes (same in React) which doesn't play well with multiple copies of the framework being present.

Resolved in https://github.com/preactjs/signals/issues/303