Description of problem:
The crash occurred after starting Gnome GMail. It will be nice to open GMail on a separate window similar to Gnome 
Google Drive.

Version-Release number of selected component:
gnome-gmail-2.2-1.fc25

Additional info:
reporter:       libreport-2.8.0
cmdline:        /usr/bin/python3 -tt /usr/share/gnome-gmail/gnomegmail.py -q
executable:     /usr/share/gnome-gmail/gnomegmail.py
kernel:         4.9.0-0.rc6.git1.2.fc26.x86_64
pkg_fingerprint: 4089 D8F2 FDB1 9C98
pkg_vendor:     Fedora Project
runlevel:       N 5
type:           Python3
uid:            1000

Truncated backtrace:
Gtk.py:83:_extract_handler_and_args:AttributeError: Handler onUserSelClose not found

Traceback (most recent call last):
  File "/usr/lib64/python3.5/site-packages/gi/overrides/Gtk.py", line 103, in _builder_connect_callback
    handler, args = _extract_handler_and_args(obj_or_map, handler_name)
  File "/usr/lib64/python3.5/site-packages/gi/overrides/Gtk.py", line 83, in _extract_handler_and_args
    raise AttributeError('Handler %s not found' % handler_name)
AttributeError: Handler onUserSelClose not found

Local variables in innermost frame:
obj_or_map: <__main__.do_preferred.<locals>.Handler object at 0x7f3b942c2b70>
handler: None
handler_name: 'onUserSelClose'

Potential duplicate: bug 1398391