In older versions of REAL Studio and Xojo, I took advantage of the (then) new Container to to convert sheet windows to more useful containers by simply swapping the Super from Window to Container. Xojo 2018r1.1 does not allow me to change a Window’s Super class to Container any longer.
Is this recent expected behavior or is a bug report in order? I discovered this while trying to work around TabPanel Cut and Paste between windows corrupting the TabPanel on Paste - <https://xojo.com/issue/52609>.
Emailed Jason to get it reopened per that thread that says that’s how we do it now because Feedback.app is broken. Hopefully this is not permanent because it’s a really poorly thought out move on Xojo’s part.
Update for people without access to Feedback: This only affects the window selected as the Default Window on your App object and is not a regression in the ability to change Windows to ContainerControls.
Actually, in my case it was far more nefarious. I had to reopen the original project in 2011r3, save as binary, open in 2016r3 and save as VCP, and then reopen that in 2018r1.1. At that point, assigning the Superclass as ContainerControl worked as expected.
I’ll just chalk this up to issues like the conversion of older projects like the yellow TextField and the magic null and doubled menu entries in the menu bars when bringing older RB/RS projects into the Xojo environment directly.