Chrome Input Flex Extra Spacing

HTML

<fieldset id="inputContent">
    <input type="Email"/>
    <input type="Submit"/>
</fieldset>

<br/>

<fieldset id="regularContent">
    <div>a</div>
    <div>a</div>
</fieldset>

<br/>

<fieldset id="hybridTextbox">
    <input type="Email"/>
    <div>a</div>
</fieldset>

<br/>

<fieldset id="hybridTextbox">
    <div>a</div>
    <input type="Submit"/>
</fieldset>

CSS

div
{
    border: 1px solid;
    min-width: 100px;
}

fieldset
{
    display:flex;
}