diff --git a/docs/specs/MQTT-SN_spec_v1.2.pdf b/docs/specs/MQTT-SN_spec_v1.2.pdf
new file mode 100644
index 000000000..ee6020d23
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diff --git a/docs/specs/mqtt-v3.1.1.pdf b/docs/specs/mqtt-v3.1.1.pdf
new file mode 100644
index 000000000..e4095f1b5
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diff --git a/rel/files/vm.args b/rel/files/vm.args
index 27c743997..a2ad9302c 100644
--- a/rel/files/vm.args
+++ b/rel/files/vm.args
@@ -58,3 +58,4 @@
 ## Tweak GC to run more often
 -env ERL_FULLSWEEP_AFTER 1000
 
+-env ERL_CRASH_DUMP log/emqttd_crash.dump