v3编译器下，textarea的focus问题

    <view>  
        <view class="container">  
            <button type="primary" plain="true" @click="test('top')">测试</button>  
            <view v-show="showTxtArea">  
                <textarea :focus="txtFocus" style="border: 1px solid red;">  
                </textarea>  
            </view>  
        </view>  
    </view>  
</template>  

<script>  
export default {  
    data() {  
        return {  
            txtFocus: false,  
            showTxtArea: false,  
        };  
    },  
    methods: {  
        test(){  
            this.showTxtArea = true;  
            this.txtFocus = true;  
        }  
    }  
};  
</script>  

点击按钮时，软键盘弹出又跑了，是bug么？