At first glance Unit PNG Fix has the benefit of being smaller (1k .js file, 1 transparent .gif). SuperSleight has a total of 3 files (two .js files and (one 3k, the other 2k, and the transparent .gif), but you can choose to use either one of the SuperSleight .js files – so if you prefer to use the mini version of SuperSleight it would just be 2k.
Both are called the same way in the <header> of the document – a conditional focusing on IE6 and below.
Unit Interactive lists the benefits of it’s script as:
- Fixes some interactivity problems caused by IE’s filter attribute.
- Works on img objects and background-image attributes.
- Runs automatically. You don’t have to define classes or call functions.
- Allows for auto width and auto height elements.
- Super simple to deploy.
24 ways introduced SuperSleight as having the following qualities:
- Works with both inline and background images, replacing the need for both sleight and bgsleight
- Will automatically apply
position: relativeto links and form fields if they don’t already have
positionset. (Can be disabled.)
- Can be run on the entire document, or just a selected part where you know the PNGs are. This is better for performance.
- Detects background images set to
no-repeatand sets the
After creating a few png transparent images and testing both methods here are my pros and cons of each:
- No need to edit .js files with image link when both are placed in the same directory (ie: root).
- Plug and play – just upload the supersleight-min.js and x.gif to your root directory, plug in the link to the file in an IE conditional and it works.
- Get IE warning about “blocked content”. Need to click top warning popup to activate supersleight.
- Comes packed with two .js files: supersleight.js and supersleight-min.js. Could be confusing to a lay-person as to which file to use, and if both are needed.
- Loads slightly slow. On pages with multiple PNGs in IE6 you see a “gray flash” before the PNG fix kicks in.
Unit PNG Fix
- Smaller size. But only by 1k.
- No popup warning that their is active content.
- Seems to load multiple images faster than superselight. A page with about 20+ transparent pngs loaded almost instantly without the “gray flash” commonly seen before the js kicks in for IE6.
- Comes with the path to the clear.gif image linked in the /images folder.
So overall, I have come to the conclusion that it seems Unit Interactive’s Unit PNG Fix is indeed a better alternative to good old SuperSleight. Let’s just keep hoping that user will keep updating their IE6’s until there is virtually no one using IE6.