id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	blockedby	blocking	notify_on_close	platform	project
820	'Session' object has no attribute 'undo'	Eric Pettersen	Conrad Huang	"Open 5uak and click the 'hide ribbon' toolbar icon.

Traceback (most recent call last):
File ""/Users/pett/src/chimerax/ChimeraX.app/Contents/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/chimerax/shortcuts/tool.py"", line 47, in button_press_cb
ks.run_shortcut(keys)
File ""/Users/pett/src/chimerax/ChimeraX.app/Contents/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/chimerax/shortcuts/shortcuts.py"", line 373, in run_shortcut
sc.run(self.session)
File ""/Users/pett/src/chimerax/ChimeraX.app/Contents/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/chimerax/shortcuts/shortcuts.py"", line 270, in run
commands.run(s, f)
File ""/Users/pett/src/chimerax/ChimeraX.app/Contents/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/chimerax/core/commands/run.py"", line 31, in run
results = command.run(text, log=log)
File ""/Users/pett/src/chimerax/ChimeraX.app/Contents/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/chimerax/core/commands/cli.py"", line 2405, in run
result = ci.function(session, **kw_args)
File ""/Users/pett/src/chimerax/ChimeraX.app/Contents/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/chimerax/core/commands/hide.py"", line 65, in hide
session.undo.register(""hide"", undo, redo)
AttributeError: 'Session' object has no attribute 'undo'"	defect	closed	blocker		Core		not a bug		chimera-programmers Elaine Meng				all	ChimeraX