FYI I just added some changes to emulation that support the following: -layout optimization (layout is not being requested as often at startup) -creationPolicy="none" in Container
*Some layout optimization* Instead of layout being triggered on a parent by every child as it is added to its parent at application startup, the layout requests are now deferred while all the mxml children are being added and then run as a single pass after that. This has a recursive benefit through the createChildren calls, and seems to make a reasonable difference in startup overhead by avoiding the unnecessary layout calls for the case when we know we are (very likely) adding multiple children in a batch. *creationPolicy="none"* I added preliminary support for emulating creationPolicy. At this point only creationPolicy=none is supported as an alternative to 'all' which is what we have by default. I added an example ViewStack launch to the mxroyale ControlsExample. This adds all its children with creationPolicy=none, except for the first one. So they are added, but their mxml children don't exist until you switch to that view, at which point they are created, bindings are executed, etc, etc. You can see this in the browser DOM if you inspect that example when you inspect the ViewStack part of the popup window. Also generally, as with emulation support to date, this change does attempt to get close to the original Flex lifecycle with the deferred content creation. There are still differences in that the royale events tend to fire in a slightly different order when considering parents and children, but generally the sequence is correct for individual UIComponents. If anyone is using emulation, please let me know if you see any issues or log them in github. So far I have tested the above against two large codebases and it appears stable (and performs a bit better for startup). The creationPolicy=none support was needed in a case where a lot of business logic was tied to the events triggered by the instantiation of deferred content in a client project, so it makes a big difference not having to rework all that, and makes startup faster as well.