Adding a pause  to an `iframe`  in `revealjs` slides makes the image squeezed

**Code to replicate**
```
. . .

<iframe class="stretch" src="plot.html"> </iframe>
```
**Screenshots**

![Plot without delay](https://user-images.githubusercontent.com/61335136/167176210-02eabe4a-1e57-4189-9862-ad422c629d6f.PNG)
![plot with delay](https://user-images.githubusercontent.com/61335136/167178515-baa1be0f-32a6-49df-8383-f2fc3ac84e32.PNG)


2022-05-06T16:46:33Z
rleyvasal
Future
open
Adding pause/delay  `. . . `  to `iframe`  in `revealjs` slides squeezes html image
https://github.com/quarto-dev/quarto-cli/issues/816