Technique F69:Failure of Success Criterion 1.4.4 when resizing visually rendered text up to 200 percent causes the text, image or controls to be clipped, truncated or obscured

Applicability

HTML, XHTML and CSS

This technique relates to 1.4.4: Resize text (Failure).

Description

The objective of this failure condition is to describe a problem that occurs when changing the size of text causes text to be clipped, truncated, or obscured, so that it is no longer available to the user. In general, this failure occurs when there is no way for a user agent's layout engine to honor all the layout hints in the HTML at the new font size. Some of the ways in which this can occur include:

• Setting the overflow property of the enclosing element to hidden
• Using absolutely positioned content
• Creating popups that aren't big enough for their content at the new font size

Examples

Example 1

The font size is set in a scalable way, but the container is set to a fixed pixel size. A gray border shows the boundaries of the text container. When the text is resized, it spills out of its container, and obsures the next paragraph.

<div style="font-size:100%; width:120px; height:100px; border: thin solid gray;"> 
  Now is the time for all good men to come to the aid of their country. 
</div>
<p>Now is the time for all good men to come to the aid of their country.</p>

Illustration of example 1:

Example 2

This example is identical to the last one, except that the container is set to clip the text. The text is no longer bleeding into the next paragraph, but now it is truncated. This is also a failure.

<div style="font-size:100%; width:120px; height:100px; overflow: hidden; border: thin solid gray;">
 Now is the time for all good men to come to the aid of their country. 
</div>
<p>Now is the time for all good men to come to the aid of their country.</p>

Illustration of example 2:

Tests