Allow an additional selection in an embed or LMS LTI embed to create a rigid bounded box for 16:9 content, to minimise or eliminate letterboxing.

<div class="uom-ui-border-box">

<div style="position: relative; padding-bottom: Calc(56.25% + 38.2px);"><iframe style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;" src="https://echo360.net.au/public/media/8e657f01-515b-4f82-9bd1-15bf409bef55?autoplay=false&automute=false%22 loading="lazy" allowfullscreen="allowfullscreen"></iframe></div>