--- a/js/src/devtools/automation/autospider.sh
+++ b/js/src/devtools/automation/autospider.sh
@@ -1,11 +1,14 @@
 #!/bin/bash
+
+# Note that the -x will be temporarily cancelled and reinstated below, so if
+# you want to eliminate this, you'll need to eliminate it there too.
+set -x
 set -e
-set -x
 
 DIR="$(dirname $0)"
 ABSDIR="$(cd $DIR; pwd)"
 SOURCE="$(cd $DIR/../../../..; pwd)"
 
 function usage() {
   echo "Usage: $0 [--dep] <variant>"
 }
@@ -138,17 +141,19 @@ RUN_JSTESTS=true
 
 PARENT=$$
 
 # Spawn off a child process, detached from any of our fds, that will kill us after a timeout.
 # To report the timeout, catch the signal in the parent before exiting.
 sh -c "sleep $TIMEOUT; kill -INT $PARENT" <&- >&- 2>&- &
 KILLER=$!
 disown %1
+set +x
 trap "echo 'TEST-UNEXPECTED-FAIL | autospider.sh $TIMEOUT timeout | ignore later failures' >&2; exit 1" INT
+set -x
 
 # If we do *not* hit that timeout, kill off the spawned process on a regular exit.
 trap "kill $KILLER" EXIT
 
 if [[ "$VARIANT" = "rootanalysis" ]]; then
     export JS_GC_ZEAL=7
 
 elif [[ "$VARIANT" = "compacting" ]]; then