Semantic elements and attributes
provide a higher level of communication. The semantics of
summary/details does not provide an explicit and
strong semantic for an image long description. This technique
provides incorrect semantics for long descriptions of images. The
HTML specification states,
summaryelement represents a summary, caption, or legend for the rest of the contents of the
detailselement, if any.
img element isn't a summary, caption, or legend.
img element is an image. An image and a long
description are peers: the same thing expressed in two different
details technique would force a visual encumbrance on
sighted users unless additional code (in the form of CSS or
hidden) were added in order to hide the visual
indicator. Please refer to the Cascading Style
documents for details of why using these techniques is a bad
summary/details technique lacks the key
functional requirement of providing a long description in a separate
details is not accessibility
supported semantics wise. HTML5 accessibility states
that that this technique,
Currently provides the same amount of semantic information to AT as a
summary/details technique for long descriptions
lacks backwards compatibility.
It is not:
For further rationale please consult the backwards compatibility document.
Any proposed solution should be easy for authors who are already
publishing content with
longdesc to retrofit their
summary/details possesses a radically
different authoring pattern than
longdesc. Because of
this as well as its on-page limitations, retrofitting with
summary/details would be difficult, labor intensive,
and error prone.
No retrofitting is required for
longdesc as it is an existing HTML feature not a new one.
No examples in the wild of accessible long text alternatives
details have been presented
for any of the use cases. No evidence exists that authors have or
will use it for accessible long text alternatives.
No evidence has been presented that
details produces more accessible
content for long descriptions than
longdesc or that
more authors would use it correctly.