Navigation block 'missing link' tooltip positioned far away from it's source in site editor

[talldan]

Description

It's easiest to show the screenshot rather than describe this:

The 'This item is missing a link' text is far away from the 'Add Link' item it should be connected to.

In testing, I could only reproduce this in the site editor.

Step-by-step reproduction instructions

1. Add a nav block in the site editor
2. Start empty
3. Click the plus button
4. Hover over the 'Add Link' text.

Screenshots, screen recording, code snippet

No response

Environment info

Mac OS, Brave, Gutenberg trunk.

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[adamziel]

This seems like an issue with the Popover component. Site editor is in an iframe, post editor isn't. .popover-slot where the tooltips are rendered is outside of the iframe. It seems like computePopoverYAxisPosition or some other function in proximity doesn't account account for the iframe's top value.

[adamziel]

iframes are only considered in when Popover receives either anchorRef or getAnchorRect, but in case of the tooltip neither of these is present. The position is based only on on anchorRefFallback. I think a sensible solution would be to still consider that an iframe may be among the parents in that case.

gutenberg/packages/components/src/popover/index.js

Lines 45 to 52 in 53374ba

	function computeAnchorRect(
	anchorRefFallback,
	anchorRect,
	getAnchorRect,
	anchorRef = false,
	shouldAnchorIncludePadding,
	container
	) {

I proposed a solution in #36876