Isolated template part editor: Height doesn't always wrap correctly

[jameskoster]

I noticed when testing with the Quadrat theme that the height of the header in the isolated template part editing view is not correct. For some reason it is way too tall:

edit-header.mp4

cc @kevin940726

[kevin940726]

Yeah, sometimes it's tricky since the height could dynamically change at any time. I'll take a look at this.

[noisysocks]

On tall viewports the height of the canvas is always too great. Would be good if we can make the canvas resize down to the intrinsic content size.

[noisysocks]

More canvas height weirdness here: #37213 (comment)

[ntsekouras]

This issues depend on each theme. For example in Quadrat there is this style.

.editor-styles-wrapper .wp-site-blocks { min-height: 100vh... } which makes the template part big. Could a simplistic solution of adding some styles like min-height: auto !important in the iframe (or by maybe first detecting such cases of vh) be enough? 🤔

The scrolling issues are related to this line and appear when we have height affecting styles to the root selector, which is the body.