Our (joomla) site template is traditional in that it has left and right columns each side of the content block.
When we place a video into the content (youtube etc), scaling we specify is ignored and the video goes full width. For example, if the scaling is set to 400px wide or 50%, when the content is rendered the video image goes to full screen width.
<p>
<iframe class="mce-item-media mce-item-iframe" src="https://www.youtube.com/embed/8J_bz7feyfY?rel=1" width="560" height="315" frameborder="0" allowfullscreen="true"></iframe>
</p>
You can see the effect here . My test is with Firefox
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[*]https://news.ccansw.org.au/index.php/the-awards/2-uncategorised/3997-test-for-jce
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