Advanced options panel should always be on top

[tdudgeon]

When the advanced options panel appears it can appear below other cells that have been added after that cell. It should always appear on top.

[tdudgeon]

Marked this as priority as its really a pain - the advanced options panel also sinks below the notebooks and cell palette panels.

[tdudgeon]

This problem remains. I tried to look at it and it looks like the popup panel appears within the bounds of the overall page, but is clipped by the components outside the main canvas window. So it looks like a z-index issue, but I couldn't work out how the z-index of the different page components is defined and just increasing the z-index of the popup to a large value did not fix the problem.

Also note that independent of resolving this, it is probably best to switch the advanced options and edit bindings popups to be modal popups as this would both solve the problem and provide better consistency across the application.

[gustavosantucho]

We've solved the z-index problem, but this brought a new coordinates problem which we didn't want to address before upgrading the libraries.
Personally I don't like using modal dialogs unless you are editing some really global settings that requires modal interaction. Modern applications avoid using modal dialogs all they can. But this is just an opinion and using modals, though disruptive, would certainly solve this particular problem.