Fix v3 to v4 crash with a variable with longer name than value

testcases/t/183-config-variables.t

@@ -95,7 +95,19 @@ EOT
 
 is(launch_get_border($config), 'none', 'no border');
 
+#####################################################################
+# test that variables with longer name than value don't crash i3 with
+# v3 to v4 conversion.
+# See: #3076
+#####################################################################
 
+$config = <<'EOT';
+set $var a
+EOT
+
+my $pid = launch_with_config($config);
+does_i3_live;
+exit_gracefully($pid);
 
 done_testing;