i‐Bench’s frame tests can do a more thorough check of your Web browser’s support for frames, including floating frames.
XHTML 1.1: The W3C phased out frames in XHTML 1.1. Frames are destined to be replaced by more powerful markup like XLink.
Jakob Neilsen has written about why frames are fundamentally flawed and their use should be avoided.
<iframe> element generates inline frames, like a simplified
Related Mozilla bug reports: Frame-Longdesc.