Using javascript's replace with wildcard to change width attribute inside string
<p>I'm trying to use <code>.replace('width=".*"', 'width="100"')</code>, since <code>width</code> could be anything in the original <code>string</code>. But at the moment that does not change anything.</p>

<p><a href="https://jsfiddle.net/bobbyrne01/8p404z5t/" rel="nofollow">https://jsfiddle.net/bobbyrne01/8p404z5t/</a></p>

<p>html</p>

<pre><code>&lt;div id="1"&gt;&lt;/div&gt;&lt;br/&gt;
&lt;div id="2"&gt;&lt;/div&gt;
</code></pre>

<p>javascript</p>

<pre><code>var fullURL = '&lt;iframe class="embedly-embed" src="https://cdn.embedly.com/widgets/media.html?src=https%3A%2F%2Fi.imgur.com%2F…key=2aa3c4d5f3de4f5b9120b660ad850dc9&amp;amp;type=video%2Fmp4&amp;amp;schema=imgur" width="406" height="720" scrolling="no" frameborder="0" allowfullscreen&amp;gt;&amp;lt;/iframe&gt;';

document.getElementById('1').textContent = fullURL;

var moddedURL = fullURL.replace('width=".*"', 'width="100"');
document.getElementById('2').textContent = moddedURL;
</code></pre>

<p>result ..</p>

<pre><code>&lt;iframe class="embedly-embed" src="https://cdn.embedly.com/widgets/media.html?src=https%3A%2F%2Fi.imgur.com%2F…key=2aa3c4d5f3de4f5b9120b660ad850dc9&amp;amp;type=video%2Fmp4&amp;amp;schema=imgur" width="406" height="720" scrolling="no" frameborder="0" allowfullscreen&amp;gt;&amp;lt;/iframe&gt;

&lt;iframe class="embedly-embed" src="https://cdn.embedly.com/widgets/media.html?src=https%3A%2F%2Fi.imgur.com%2F…key=2aa3c4d5f3de4f5b9120b660ad850dc9&amp;amp;type=video%2Fmp4&amp;amp;schema=imgur" width="406" height="720" scrolling="no" frameborder="0" allowfullscreen&amp;gt;&amp;lt;/iframe&gt;
</code></pre>