작성: Carlo Alberto Ferraris (개발자), 날짜: 11월 6, 2008 · 고유 주소

From version 0.17 onward, the default zooming control has changed to be consistent with firefox's built-in one.
As such, you now has to do ctrl+wheel to zoom (this is the same command used on webpages) and wheel to scroll vertically: this is meant to ease new users that may be used to the standard command.
You have therefore to choose: you can use the new command (rest assured that no-one better than me knows how painful it is: I originally coded this extension for myself and I've been using it with the old control for years!) or go in about:config and set extensions.imagetweak.legacyscrolling to true (this is explained in detail in the online help http://cafxx.strayorange.com/ImageTweak%20Help).
Hope this fixes it for you.