Vue.js 写入计算值时出错，但我没有写入任何值

我设置了一个标志foundInBrowser，它通知我条目'aaa'是否存在于本地存储中.点击input toggle可添加/删除该条目，进而自动更新标志:

<template>
  <q-toggle 
    v-model="foundInBrowser" 
    checked-icon="check" 
    color="red"
    :label="`${foundInBrowser ? '' : 'not'} registered in browser`" 
    unchecked-icon="clear"
    @click="registerInBrowser" 
  />
</template>

<script>
    const registerInBrowser = () => {
        // toggle the existance of the localstorage entry
        if (foundInBrowser.value) {
            localStorage.removeItem('aaa')
        } else {
            localStorage.setItem('aaa', person.value?.ID as string)
        }
    }
    const foundInBrowser = computed(() => localStorage.getItem('aaa') !== null)
</script>

当点击切换时，我在控制台中得到一个错误:

Write operation failed: computed value is readonly

我不理解这个错误:我没有试图在任何地方写到foundInBrowser.