In Mozilla, when the mouse is rolled over the menu and the mouse crosses over the IFrame border that runs behind the menu, a menu mouseout is triggered, which informs HierMenus that the mouse has left the menu. If the mouse continues, i.e., if it "clears" the border of the IFrame, a mouseover is triggered that then re-indicates to HM that the mouse is once again on the menu. Thus, if your MilliSecondsVisible settings are set to small amounts and ClickKill is false, the menu may disappear when you cross over the unseen IFrame border. (And if you stop the mouse exactly over the IFrame border, the menu will eventually disappear when MilliSecondsVisible is elapsed.

In Safari 1.2, the problem is similar to the Mozilla issue, except that the mouseover for the menu is not refired when the mouse clears the IFrame border. Thus, the menu is always hidden when MilliSecondsVisible elapses (unless the user quickly moves back outside the IFrame border). Even if ClickKill is set, the visible portion of the menu that happens to overlay the IFrame will be unusable; Safari treats it as if it is indeed being covered by the IFrame.

In Safari 1.3, the mouseout is not triggered when the mouse rolls over the IFrame border that runs beneath the menu. This is good; the menus are therefore visible and usable over the IFrame. However, the mouseout for the menu itself will then not actually be triggered until the mouse exits both the menu and the IFrame, and therefore the menus will appear to be "sticky," i.e., they will not hide as and when you expect. As long as the mouse remains within the IFrame border, the last menu that was displayed will remain in view.

An example page demonstrating the root problem can be viewed by clicking the link below:

IFrame Hiding Elements

And an example of how the problem effects HierMenus can be found on the IFrame Masking HM Example Page.

Other suggestions are requested. Please use this link to send mail if you have any insights and would like to share them:

IFrames and Menus