Bug 167198

Summary: [GTK] height:100% breaks frame-flattening
Product: WebKit Reporter: Milan Crha <mcrha>
Component: WebKitGTKAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: bugs-noreply
Priority: P2    
Version: WebKit Local Build   
Hardware: Unspecified   
OS: Unspecified   
See Also: https://bugzilla.gnome.org/show_bug.cgi?id=777479

Description Milan Crha 2017-01-19 04:35:52 PST
Moving this from a downstream bug report:
https://bugzilla.gnome.org/show_bug.cgi?id=777479

Evolution uses frame flattening and shows messages in iframe-s. Having frame flattening enabled and this top web page:

	<html>
	  <body>
	  <iframe style="height:10px" src="file:///tmp/a.html">
	  </body>
	</html>

and the /tmp/a.html being

	<html style="overflow:auto;">
	  <body style="height:100%;overflow:auto;">
	    Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod
	    tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam,
	    quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo
	    consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse
	    cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat
	    non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
	  </body>
	</html>

causes the iframe being only 10 pixels height and the content being scrollable (with scroll bars). The downstream bug report has a screen shot of it.

Changing /tmp/a.html body's style to not include height:100% fixes the issue and the iframe is expanded based on its content.

I have a standalone application which uses pure WebKitGTK+ exposing this issue. I can share it, if it would be useful for you.