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Re: browser zoom VS text zoom

for

From: Alastair Campbell
Date: Aug 6, 2013 3:19AM

I think it's been a very useful discussion for two reasons:

1. Responsive web design (RWD) is a current trend, and although few
sites are currently responsive, a lot of sites currently in
development will be. RWD has a big impact on how browser zoom works,
for the better IMO.

2. WCAG 2.0 was released before media queries were reliable in current
browsers, and zoom was universally the default in desktop browsers. I
think it might be time to start refining the success criteria for SC
1.4.4.

Jared commented on my post (the pro-zoom one) that he would structure
passing WCAG2 1.4.4 as:

Level AA
- Zoom at 200%
- Text sizing at 150%

Level AAA
- Zoom at 200% with no horizontal scrolling
- Text sizing at 200%

Personally, given the ease of supporting zoom in RWD I would structure
a pass at Level AA as either:
- Zoom at 200% with no horizontal scrolling or loss of functionality.
- Text-sizing at 200% without loosing content or functionality.

Admittedly these methods (allowing for text-sizing and RWD) are not
mutually exclusive, you could use media queries without full RWD, and
in RWD you could buffer the text to allow for some text expansion.
Some, probably not 200% though.

Jared pointed out that many of his clients have real difficulty
allowing for 200% increase, and I've had similar experiences,
especially for CMS driven sites where the content varies. The key
difference now is that RWD provides a way of dealing with the
situation of having a full screen and still zooming in. Depending on
the layout you can drop columns, or hide menus behind a button, or
various other things.

Given how easy it is to support a good zoom experience in RWD (which
many developers are using and spending time testing anyway), I don't
think 200% zoom without loosing content/functionality is a hardship.
However, there still needs to be the non-RWD clause as well...

-Alastair