Describe the bug

After updating the rematch version to 2.1.1, my working repo is broken with an error Cannot add property loading, object is not extensible, after some debug, I cannot find the root cause of this bug, so could you please confirm if this is a bug? Thanks!

Reproduce Link

• GitHub Repo: https://github.com/upupming/rematch-obj-not-extensible
• CodeSandbox: https://codesandbox.io/s/github/upupming/rematch-obj-not-extensible/tree/main/

To Reproduce

See the runtime error in the codesandbox:

Expected behavior

Screenshots

Desktop

• OS: macOS
• Browser: Chrome Latest
• Version: 2.1.1

Additional context

I find that I can reproduce this error on the example rematch-example-all-plugins-react-ts too, simply change these lines:

to:

immerPlugin(),