Jonathan has created a simple JavaScript “sevenup” that help rid the world of IE6 with one line of code. Just call the script in the header, when your webpage is viewed in IE6 or older, a pure-CSS lightbox pops up, suggesting that the user upgrade their outdated web browser. When NOT viewed in IE6/older, the user has no idea the script is there. You can either require the upgrade, or let them through with a warning.

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