attn @mdehoon

Does this also happen with regular Python (i.e. not IPython)?

Yes and no: yes, the same message is printed in the terminal (instead of opening a dialog as is usual in Mac OS X Yosemite), but no it does not seem to block anything (the figure still responds to the mouse [like with IPython]), and closing the figures makes pyplot.show() continue normally (which gives back the shell prompt back, unlike in IPython).

Is this a duplicate of #3476 ?

This is not a duplicate of that issue. The file can be saved normally. The problem on OS X (in the condition I described) is that after the file is saved, the IPython prompt is blocked (probably because the terminal is waiting for the disk image password—instead of having had a window pop up for this and be closed by the user).

PS: I found a way of making Python not block after it displays Enter password to access "…": Ctrl-C releases it (it only prints KeyboardInterrupt, nothing else.

I can't work out how to reproduce this - @lebigot is this still an issue, and if so could you post a step by step guide to reproduce it?

I did try to reproduce the issue on macOS 13.1, but I can't find my recently mounted (and then ejected) disk image in the figure Save dialog. The dropdown menu with recent items used to show it and it could be selected (which prompted the user for the password of the disk image).

I am closing this, then, especially since I'd be surprised if most users haven't switched to Jupyter!

PS: for reference, the step by step procedure to reproduce this is:

1. Launch Disk Utility so as to create a new disk image.
2. Select File > New Image… > Blank image.
3. Create an encrypted image. Do not save the password.
4. (Maybe: add a file to the new disk, so as to create some "activity" in the new disk.)
5. Eject the new disk.

Before, the (now unmounted) new disk would appear in the (expanded) Save dialog of figure, with the macOS backend, and it could be selected. This would prompt the user for the disk image password.

This seems like both reasonable behavior and something that we have fully out-sourced to OSX (as we are using the native file browser UI).