使用这样的表单时注意到一个问题：
<div class="row">
<iron-icon icon="my-icons:person"></iron-icon>
<paper-input required id="firstName" value="[[firstName]]" label="First name" on-value-changed="_firstNameChanged">
<iron-icon icon="clear" hidden$="[[!firstName]]" slot="suffix" class="input-icon" on-click="_clearInput"></iron-icon>
</paper-input>
</div>
<div class="row">
<iron-icon icon="my-icons:person"></iron-icon>
<paper-input required id="lastName" value="[[lastName]]" label="Last name" on-value-changed="_lastNameChanged">
<iron-icon icon="clear" hidden$="[[!lastName]]" slot="suffix" class="input-icon" on-click="_clearInput"></iron-icon>
</paper-input>
</div>
<div class="row">
<iron-icon icon="communication:phone"></iron-icon>
<paper-input required id="phone" value="[[phone]]" label="Phone" type="tel" on-value-changed="_phoneChanged">
<iron-icon icon="clear" hidden$="[[!phone]]" slot="suffix" class="input-icon" on-click="_clearInput"></iron-icon>
</paper-input>
</div>
<div class="row">
<iron-icon icon="communication:email"></iron-icon>
<paper-input required id="email" value="[[email]]" label="Email" type="email" on-value-changed="_emailChanged">
<iron-icon icon="clear" hidden$="[[!email]]" slot="suffix" class="input-icon" on-click="_clearInput"></iron-icon>
</paper-input>
</div>
<div class="row">
<iron-icon icon="communication:email"></iron-icon>
<paper-input required id="email" value="[[email]]" label="Email" type="email" on-value-changed="_emailChanged">
<iron-icon icon="clear" hidden$="[[!email]]" slot="suffix" class="input-icon" on-click="_clearInput"></iron-icon>
</paper-input>
</div>
我得到一个表单，其中禁用了默认情况下在简单输入表单中启用的选项卡箭头（请参见下面的屏幕截图）。
问题是：有没有办法让他们工作？
我试过了：
- 表索引
- 将其包装在标签中
- 删除所有图标标签
- 标签中的纸张输入
截图：
