WARNING
Soo… this has the potential to break the designer (if you press preview), so be careful about the dark magic i am about to share…
But it has the great power to code html and even javascript in perspective!
BEHOLD:
iframe src can render strings as html!
data:text/html,<button onclick=alert('MAGIC')>Magic</button>
It works with <script>
BUT this seems to freeze the designer if you press preview mode.
You cant communicate with the components outside the iframe (i think cuz its an iframe afterall, unless perspective has a window message handler that can be called in js) , but still might be some fun things to try with this