Room Previews now have Fit Width and Fit Height Scaling Modes
Insert a Room Preview by going to the Element menu - All - Room Preview or Element - Embeds - Room Preview. Room previews are live feeds of / automatic links to rooms in ohyay.
Click on the Room Preview element to pull up its settings in the right-hand menu. Under the Element category, click on Auto next to Scale Mode and select either Fit Width or Fit Height.