Inkscape crashes when opening files / unable to add object to the hash.

[R.Koebler]

When opening several files in inkscape, inkscape crashes. This is *very* annoying, since it makes it nearly impossible to work with several svgs in parallel. Usually, inkscape crashes after opening the 2nd or 3rd file.

Tested version:

- Inkscape 0.92.2 on Linux (NixOS, but it's the same on Debian)
- Inkscape 0.92.1 r15371 on Debian Jessie
- did not happen with 0.48

This is completely reproducible here, and occurs when:

- 2 or more files are opened from the commandline, e.g. ``inkscape a.svg b.svg``
- opening 2 or more files from with the inkscape-menu

In the console, I then get the following messages:

  ** (inkscape:27956): WARNING **: master 0x5340440: unable to add object 0x62a4a00[DialogAlignDistribute] to the hash. There already is an item with that name (0x58b22a0).

  (inkscape:27956): Gtk-CRITICAL **: IA__gtk_widget_show_all: assertion 'GTK_IS_WIDGET (widget)' failed

  (inkscape:27956): GLib-GObject-WARNING **: invalid uninstantiatable type '(null)' in cast to 'GtkWidget'

  (inkscape:27956): GLib-GObject-CRITICAL **: g_object_get_qdata: assertion 'G_IS_OBJECT (object)' failed

  (inkscape:27956): GLib-GObject-CRITICAL **: g_object_get_qdata: assertion 'G_IS_OBJECT (object)' failed

  Emergency save activated!
  Emergency save completed. Inkscape will close now.
  If you can reproduce this crash, please file a bug at www.inkscape.org
  with a detailed description of the steps leading to the crash, so we can fix it.

I guess the problem is the first message: master 0x5340440: unable to add object 0x62a4a00[DialogAlignDistribute] to the hash. There already is an item with that name (0x58b22a0).

This is probably similar to https://bugs.launchpad.net/bugs/1694673 and https://bugs.launchpad.net/bugs/1661573

[Qantas94Heavy (qantas94heavy)]

Thanks for reporting this issue. The messages appear similar enough that I'm fairly sure this has the same root cause. Closing as dupe of bug 1661573.