CSS - Transition not smooth in safari
<p>A simple transition on font-size is resulting in stuttering in safari, where as it's smooth in chrome and firefox. Is this a safari issue, a webkit issue or something else? Any hack is appreciated.</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
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<pre class="snippet-code-css lang-css prettyprint-override"><code>input {
  font-size: 1vw;
  transition: font-size 0.4s;
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  border: none;
  box-shadow: none;
  outline: none;
}
input:focus {
  font-size: 1.2vw;
}</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;input type="text" placeholder="hello" value="hello"&gt;&lt;/input&gt;</code></pre>
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