The clickthrough behaviour used to be the default in NeXTstep (and it was one of the things which I misliked not having when switching from my Cube to my work M

The clickthrough behaviour used to be the default in NeXTstep (and it was one of the things which I misliked not having when switching from my Cube to my work Mac and ThinkPad portable ages ago). The apps it works in are probably written in Cocoa née "Yellow Box" (allegedly so named because Bill Gates stated that rather than write apps for NeXT APIs he would instead....) The way I fix it when using my Mac these days is to only use apps written using Objective-C and so forth.