Avoid AlphaImageLoader Filter

What is AlphaImageLoader?

If you have ever run a website speed test before 2014, you may have come across a suggestion to avoid AlphaImageLoader filter, but what does that even mean? Well, besides being a very confusing combination of words to read, AlphaImageLoader has to do with the browser not supporting images (.pngs) with transparent backgrounds, specifically with the Internet Explorer 6 browser. Internet Explorer 6 was retired in 2014, so the issue is not relevant today, but at the time it was implemented to fix transparent PNG issues, but sometimes caused the browser to stall and lock up completely. Not the best solution when it comes to providing a great user experience at the time. So, at the time, if you came across the AlphaImageLoader filter, the best approach was to ignore it completely, and work with a different PNG version, if possible. Thankfully, with modern browsers and CMS solutions, you should not have to deal with issues like this anymore.



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