JotForm Embed: JotForm widgets don't display in embedded form

### Context and steps to reproduce

Some elements from JotForm embeds do not display correctly on WordPress.com sites. For instance, the “Short Scrollable Terms” widget from JotForm does not appear when embedded on a WordPress.com page.

1. Create a page/post on your WordPress.com site.
2. Copy/paste this JotForm onto the page: https://form.jotform.com/250972602980057 so that it embeds.
3. View the page with the JotForm embed. The content of the embed will not display properly.

### Site owner impact

Fewer than 20% of the total website/platform users

### Severity

Minor

### What other impact(s) does this issue have?

No revenue impact

### If a workaround is available, please outline it here.

Form block: https://wordpress.com/support/wordpress-editor/blocks/form-block/

### Platform

Atomic, Simple

Reproduce the issue by creating a WordPress.com page or post and embedding the provided JotForm URL, then verify the Short Scrollable Terms widget and other embed content. Use the Form block workaround as a comparison; the work is done when the JotForm embed displays its content correctly on WordPress.com sites.

Written by the indexing model from the issue text.