However, sometimes people deliberately leave the controls attribute off the media
element because they’re using the media element as part of a web page presentation
and want the media to play as soon as the page loads—regardless of whether scripting
is enabled or not. They’ll remove the controls attribute, and add autoplay and possibly
the loop attribute (covered later in the chapter). If scripting is enabled, the default media
control isn’t added to the page—but if scripting is disabled in the user’s browser, ac-
cording to the HTML5 specification, the browser is then supposed to add the control,
by default.
This is an unusual event without precedent in web development. It’s comparable to
the browser overriding CSS to display hidden or collapsed fields if scripting is disabled,
regardless of what the developer or author wants.
Currently, Opera is the only browser that actually provides a visible control if scripting
is disabled. The other browsers are technically in violation of the HTML5 specification,
though I couldn’t find bugs for any of the browsers asking for this behavior. There are,
however, bugs filed against the HTML5 specification to remove this unusual fallback
feature. Since we don’t know if the bugs will result in a change to the specification or
not, you’ll want to test your use of the HTML media elements with scripting enabled
and disabled, regardless of whether you use scripting in your page or not.
Another browser foible: if scripting is disabled, Firefox doesn’t currently
display a control UI (User Interface) even if you do provide the
controls attribute. You’ll need to use the right mouse button context
menu to control the media. More on this in
Chapter 2.
Support for Multiple Media File Types
Figure 1-1 showed Example 1-1 in Firefox, using the default control UI that Firefox
provides. You’re probably curious to see what the default styling is for the audio element
control in another browsers, such as Internet Explorer 9.x. If you open the page in IE
9, though, all you’ll get is a black box with a small red x signaling broken content.
The reason you received an indication of broken content is because the audio element
only features one type of audio content—an audio file encoded as Ogg Vorbis. Micro-
soft does not support Ogg Vorbis in Internet Explorer.
You can play Ogg Vorbis files in IE 9 if you install supporting software.
I’ll cover this in more detail in the next section.
4 | Chapter 1: HTML5 Audio and Video Elements: By-Default
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