diff --git a/doc/internals/listener-states.fig b/doc/internals/listener-states.fig
new file mode 100644
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+#FIG 3.2  Produced by xfig version 3.2.7a
+Portrait
+Center
+Metric
+A4
+100.00
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+1200 2
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+4 1 0 50 -1 16 7 0.0000 4 120 300 3555 405 add()\001