crash after making selection with square lasso

opened jpeg
used square selection tool
crash
$ pinta

(Pinta:3188): GLib-GIO-CRITICAL **: 07:27:33.961: g_dbus_proxy_new: assertion 'G_IS_DBUS_CONNECTION (connection)' failed

(Pinta:3188): GLib-GIO-CRITICAL **: 07:27:33.961: g_dbus_proxy_new: assertion 'G_IS_DBUS_CONNECTION (connection)' failed
free(): invalid pointer
Stacktrace:

  at <unknown> <0xffffffff>
  at (wrapper managed-to-native) GLib.SList.g_free (intptr) <0x0005f>
  at GLib.ListBase.Empty () <0x0013c>
  at GLib.ListBase.Dispose (bool) <0x0000f>
  at GLib.ListBase.Finalize () <0x0001d>
  at (wrapper runtime-invoke) object.runtime_invoke_virtual_void__this__ (object,intptr,intptr,intptr) <0x00068>

Native stacktrace:

 /usr/bin/mono(+0xc8514) [0x5616974f1514]
 /lib/x86_64-linux-gnu/libpthread.so.0(+0x12890) [0x7fc567752890]
 /lib/x86_64-linux-gnu/libc.so.6(gsignal+0xc7) [0x7fc567175e97]
 /lib/x86_64-linux-gnu/libc.so.6(abort+0x141) [0x7fc567177801]
 /lib/x86_64-linux-gnu/libc.so.6(+0x89897) [0x7fc5671c0897]
 /lib/x86_64-linux-gnu/libc.so.6(+0x9090a) [0x7fc5671c790a]
 /lib/x86_64-linux-gnu/libc.so.6(cfree+0x4cc) [0x7fc5671cee1c]
 [0x415b5930]

Debug info from gdb:

=================================================================
Got a SIGABRT while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
=================================================================

Aborted (core dumped)

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: pinta 1.6-2
ProcVersionSignature: Ubuntu 4.15.0-42.45-generic 4.15.18
Uname: Linux 4.15.0-42-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.5
Architecture: amd64
CurrentDesktop: LXDE
Date: Mon Dec 10 07:28:38 2018
InstallationDate: Installed on 2018-03-02 (283 days ago)
InstallationMedia: Lubuntu 17.10 "Artful Aardvark" - Release amd64 (20180105)
PackageArchitecture: all
SourcePackage: pinta
UpgradeStatus: Upgraded to bionic on 2018-07-25 (137 days ago)