Many elements of Dynamic HTML (client-side scripted HTML,
which is usually accomplished with Javascript) cannot be made directly
accessible to assistive technologies and keyboards, especially when the
onMouseover command is used. If an onMouseover (or similar) element does not
contain any important information (e.g. the script causes a button to
"glow"), then there is no consequence for accessibility. If this
scripted event reveals important information, then a keyboard-accessible
alternative is required.
Text equivalents of frames should be provided so that
their contents and the relationships between frames make sense. This also means
that when the contents of a frame changes, the description, if any, must change
too. You can’t do that if an img is inserted directly into a frame. Therefore,
the source ("src") of a frame should always be an HTML file, and any
images, along with their text alternatives, should be placed in the HTML file.
A text-only version of the page should be used only when
there is no other way to make the content accessible, or when it offers
significant advantages over the "main" version for certain disability
types. It must be kept up-to-date with the primary version.
When components (e.g. plug-ins, scripts) are not directly
accessible, an alternative needs to be provided
Scripts (e.g. JavaScript pop-up menus) should either be
directly accessible to assistive technologies (keyboard accessibility is a good
measure of this), or an alternative method of accessing equivalent functionality
should be provided (e.g. a standard HTML link).
