For many extensions, use those that you find at Jujuland. In the case of Adblock Plus it is best to go here: http://adblockplus.org/en/kmeleon for the latest version. Download it, and when you unzip it, point it to the folder where k-meleon.exe is stored. When you start K-Meleon, it will ask you subscribe to one or another groups, just choose one. In the case of NoScript, go to Jujuland.
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