Description of problem:
When using a BFO install of rawhide (future f24), I get an error from anaconda when trying to return from custom partition assignment.  The error is
Attribute error: 'Expander' object has no attribute 'members' - Anaconda
The exception chain is
accordian, custom, custom, custom, utils, 
And the error is in line 269 of _run_once_oneself._func of utils.py

It happens when I am assigning existing partitions to /boot and /.  It moves the first partition, / or /boot, from unkown linux to the new allocation, but the second partition, whether it is /boot or /, causes this error.  Whether I press 'done' or 'update page information' after I have completed the second partition.

These are an ext4 partition I am assigning to /, and an ext2 partition I am assigning to /boot.  I request that they be formatted.

Version-Release number of selected component (if applicable):
Anaconda 24.11-1

How reproducible:
Every time.


Steps to Reproduce:
1.  BFO install of rawhide x86_64
2.  Select existing partitions for assignment to new / and /boot for install
3.  

Actual results:
Above error

Expected results:
Return to main install page for selection of software and continue to successful installation.

Additional info:
The download from BFO tends to be very slow (as low as 30 kbytes / second), so takes several hours to get the required boot data.  Once in a while it is fast, but that seems to be 1 in 10 or less tries.  This limits how many times I can try the install, as I usually set it up to run overnight, and install in the morning.  Unfortunately, there is usually an error in the system when it tries to boot with a slow start, and it gets an unable to find /dev/root.  I guess what I'm saying is that testing this is very time consuming and hit or miss.

Before the error in https://bugzilla.redhat.com/show_bug.cgi?id=1305287, these partitions showed as Fedora 20, and I could successfully complete this portion of the install, to get to the error mentioned there.  When that error was in the base minimal install, it didn't seem to do anything to these partitions, and so this error didn't occur.  Once that error moved to the optional packages, it seems to have done something to these partitions before it found the dependency issue in the selected packages, and I am now getting this error.

I have moved to a root window (great idea!), and deleted the lock on anaconda, and killed X, in order to run the install up to three times, but the error is very consistent.  I was hoping that some cruft would be left around on successive tries, and the install would get past the error.