Basically, this bug causes elements inside of IFRAMES in Mozilla, Firefox, Netscape, and Safari browsers to “switch places” or load into the wrong frame. This can make it look as if a vertical ad, such as a skyscraper (160×600), is loading into a horizontal ad spot, such as a leaderboard (728×90), to give just one example.
Initially, you might think that someone scheduled the ad to the wrong position in your ad server, except the page isn’t breaking. If the skyscraper loaded in the leaderboard spot, the space there would push down the content by 600 pixels instead of 90. This bug will make it seem as if the top of the skyscraper is showing inside of a frame/window that’s shaped like a leaderboard (without stretching the graphics to fit).
This bug has been around for years. The best explanation that I’ve been able to find is that these browsers are getting confused as to which content to display in the IFRAME when a page is reloaded. This is thought to happen when people are refreshing pages looking for their ads. Maybe they are internal users trying to get a screenshot.
In other cases, I’ve seen internal users that were not refreshing have this problem in Safari and Firefox. I believe this to be because of their cache settings. When a browser refreshes, it retrieves some items from it’s cache, then calls out to the ad server and other servers for items that need to be updated, such as ads. Since the actual IFRAME may still reside in the cache, the browser is trying to save time by reusing the code for that object. It doesn’t know that most IFRAMES, especially from 3rd party ad tags, are not going to house the same content each time it loads. Think about it this way. The browser sees two things named “IFRAME” and remembers that one came from the ad server…so to save time, it makes the assumption that the IFRAME will be loading the same thing from the same source, right? Well, it’s wrong. It was a leaderboard last time, and is now a skyscraper this time.
If you come across this bug, rest assured that there’s really no fix as of right now except to target your third party tags away from Safari, Firefox, Mozilla, and Netscape. I know that hurts when you might already be padding for the report discrepancy that is so rampant with 3rd party servers. The other choice you have is to keep an eye on the feedback. Is it all from internal users who refresh while looking for their ad? If you can manage their expectations, and their feedback, then just let it ride.
Here are some links that document these problems. Unfortunately, these are open source developers. No one truly owns these problems, so there’s no company to “beat up” about it until it gets fixed. Which is why we all just have to work around it for now.
If anyone has advice on how they are handling this, please leave a comment below!
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