Text-overflow: ellipsis causes flex item to overflow flex container
<p>I have two columns inside a flex container. One of the columns (orange one) contains an avatar and its width should be exactly 10% of container.</p>

<p>Another column (blue one) contains panel, and the panel's title could be very long, so I should truncate it via css. This picture shows what I expect:</p>

<p>What I expect:</p>

<p><img src="https://i.stack.imgur.com/Hniii.png" alt="What I expect"></p>

<p>But when I'm trying to do <code>text-overflow: ellipsis</code>, my second row is becoming wider than the flex container. Here is example of this behaviour:</p>

<p><a href="https://jsfiddle.net/8krtL9ev/1/" rel="nofollow noreferrer">https://jsfiddle.net/8krtL9ev/1/</a></p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-css lang-css prettyprint-override"><code>.container {
  background: #ddd;
  width: 400px;
  height: 200px;
  padding: 10px;
  display: flex;
}

.row1 {
  background: red;
  flex-basis: 10%;
  flex-shrink: 0;
}

.row2 {
  background: blue;
  flex-basis: 90%;
  margin-left: 10px;
  padding: 10px;
  display: flex;
}

.panel {
  background: green;
  flex-basis: 50%;
  overflow: hidden;
}

.panel-title {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="container"&gt;

  &lt;div class="row1"&gt;
  &lt;/div&gt;

  &lt;div class="row2"&gt;
    &lt;div class="panel"&gt;
      &lt;div class="panel-title"&gt;
        &lt;span&gt;Lorem ipsum. Lorem ipsum. Lorem ipsum. Lorem ipsum. Lorem ipsum. Lorem ipsum. Lorem ipsum.&lt;/span&gt;
      &lt;/div&gt;
    &lt;/div&gt;
  &lt;/div&gt;
&lt;/div&gt;</code></pre>
</div>
</div>
</p>

<p>How can I solve this problem?</p>