If you open the "Report Broken Web Site" tool, you can't scroll any of the iframe elements with a scrollwheel (license agreement, submitted report view at the end of the wizard). Also, you can't scroll the hierarchy view when adding a bookmark.
Not an iframe issue, a window type issue. In nsMacWindow, the scroll CE handler is only registered if mWindowType == eWindowType_toplevel. Scroll wheel support was added by pinkerton in rev 1.95 of nsMacWindow.cpp, bug 71045. There's your daily blast from the past. There doesn't appear to be a good reason for it to be in the conditional, other than that it was a convenient place to add the code. I'm either going to remove the conditional (installing the handler regardless of window type) or expand the list of window types that get the handler.
Created attachment 196852 [details] [diff] [review] Patch This installs the scroll wheel event handler on all window types except invisible, plugin, and java. For the bug reported here, it needs to be on dialog, and for the bookmark add UI, it needs to be on sheet. Note that popup gives scroll wheel control of <select> elements.
Comment on attachment 196852 [details] [diff] [review] Patch r=mano
Time from open to close = 1 hour. That includes 15 minutes I spent on the bus.
This is a pretty noticeable issue on the Mac. I recommend that we take this fix for 1.8b5.
*** Bug 236909 has been marked as a duplicate of this bug. ***
*** Bug 312892 has been marked as a duplicate of this bug. ***