got error when use @Mutation in app.config.errorHandler

[LitStronger]

runtime-core.esm-bundler.js:408 Uncaught (in promise) Error: Maximum recursive updates exceeded. This means you have a reactive effect that is mutating its own dependencies and thus recursively triggering itself. Possible sources include component template, render function, updated hook or watcher source function.
at checkRecursiveUpdates (runtime-core.esm-bundler.js:408)
at flushJobs

the code
in main.ts

app.config.errorHandler = (err, vm, info) => {
  console.log(err, vm, info);
  errorStore.commitCount(1);
};

in store.ts

import { VuexModule, getModule, Module, Mutation } from "vuex-module-decorators";
  @Mutation
  commitCount(extra: any) {
    this.count += extra;
}

who can tell me why?

[LitStronger]

[cuebit]

This is unrelated to vuex-module-decorators.