Why is flex affecting font size on iOS?

Question

I'm pretty shocked after confirming that font size is affected somehow while using flexbox on Safari iOS

iOS

Desktop

Code

a {
    font-size: 14px;
}

a + a {
    margin-left: 1em;
}

.flex {
    display: flex;
}

.float > a {
    float: left;
}

.float:after {
    content: "";
    display: block;
    clear: both;
}

<div>
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
</div>

<div class="flex">
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
</div>

<div class="float">
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
    <a href="#">hola</a>
    <a href="#">adios</a>
</div>

What am I missing here?, is this a bug?

Answer 1

So, the issue with the font-size appears for both, flex and float:

https://stackoverflow.com/a/22417120/94144

Adding this fixed it:

a {
    text-size-adjust: 100%; 
    -ms-text-size-adjust: 100%; 
    -moz-text-size-adjust: 100%; 
    -webkit-text-size-adjust: 100%;
}