User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en) AppleWebKit/417.9 (KHTML, like Gecko) Safari/417.8 Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8) Gecko/20051111 Firefox/1.5 On the attached reduction, you'll see that Firefox 1.0 calculates layerX/Y to be the same as pageX/Y or clientX/Y, while Firefox 1.5 calculates layerX/Y to be pageX/Y + (1,1). Related bugs: 321119, 290428, and 296036. Reproducible: Always Steps to Reproduce: 1. Look at the layerX and pageX properties from any mouse event, and you'll see they're different. Actual Results: layerX != pageX on the attached reduction. Expected Results: layerX == pageX on the attached reduction.
Ok, so as mentioned on #developers: 1) the 1.7 (Firefox 1.0) -> 1.8 (Firefox 1.5) change that introduced the bug was the patch from bug 290428 2) the 1.8 -> trunk change that fixed the bug was the patch in bug 296036 This means this bug is fixed for Firefox 3. As such, marking WFM.