With the same disk layout that caused https://bugzilla.redhat.com/show_bug.cgi?id=1062842 , after applying the patch for that bug, I hit a subsequent crash on the Reclaim Space spoke (resize.py ). I was able to work around it by deleting the partition I wanted to delete with fdisk, and skipping the reclaim space step, so I don't have the layout to reproduce the bug any more, but I did save the complete traceback, which is attached.

anaconda 21.20-1 exception report
Traceback (most recent call first):
  File "/usr/lib/python2.7/decimal.py", line 1590, in __float__
    return float(s)
  File "/usr/lib/python2.7/site-packages/pyanaconda/ui/gui/spokes/lib/resize.py", line 249, in _setup_slider
    self._resizeSlider.set_range(int(ceil(device.minSize)), int(device.size))
  File "/usr/lib/python2.7/site-packages/pyanaconda/ui/gui/spokes/lib/resize.py", line 291, in _update_action_buttons
    self._setup_slider(device, Size(bytes=obj.target))
  File "/usr/lib/python2.7/site-packages/pyanaconda/ui/gui/spokes/lib/resize.py", line 481, in on_selection_changed
    self._update_action_buttons(self._diskStore[itr])
ValueError: invalid literal for float(): 12.12 GiB
 
Local variables in innermost frame:
s: 12.12 GiB
self: 12.12 GiB