Strict mode keeps old watchers and hinders performance

Version

4.0.2

Reproduction link

https://playcode.io/2226769

Steps to reproduce

Change STRICT_MODE to true

What is expected?

Some performance drop thanks to strict mode

What is actually happening?

The performance drop is much bigger, because 'enableStringMode' creates watchers and never stops them

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Dynamically registering modules makes things worse since it resets the store and creates even more watchers