Regarding the flashing vertical bar that appears after the Vue selection box gets focus, this is usually caused by the browser's default text box cursor style. This can be solved with the following CSS code:

input:focus {
    outline: none; /* 隐藏默认的聚焦边框 */
}

input::-webkit-input-placeholder {
    color: transparent; /* 隐藏光标 */
}