diff --git a/src/common/spawn.c b/src/common/spawn.c
index 6e8e7c51..c9b49286 100644
--- a/src/common/spawn.c
+++ b/src/common/spawn.c
@@ -23,6 +23,8 @@ reset_signals_and_limits(void)
 
 	/* Restore ignored signals */
 	signal(SIGPIPE, SIG_DFL);
+	signal(SIGUSR1, SIG_DFL);
+	signal(SIGUSR2, SIG_DFL);
 }
 
 static bool
diff --git a/src/server.c b/src/server.c
index 503838cd..76a4acf5 100644
--- a/src/server.c
+++ b/src/server.c
@@ -328,6 +328,18 @@ server_init(struct server *server)
 	 */
 	signal(SIGPIPE, SIG_IGN);
 
+	/*
+	 * Some day in the future, signal handlers may be assigned to these
+	 * SIGUSR? signals. To give users a chance to develop extensions bound
+	 * to these signals, make signalling labwc with SIGUSR[12] "safe" by
+	 * ignoring these signals (as one may accidentally SIGUSR a labwc
+	 * process not supporting such extensions).
+	 * When signal handler assignment(s) is made, the corresponding
+	 * signal(SIGUSR?, SIG_DFL); call(s) in spawn.c can be removed.
+	 */
+	signal(SIGUSR1, SIG_IGN);
+	signal(SIGUSR2, SIG_IGN);
+
 	/*
 	 * The backend is a feature which abstracts the underlying input and
 	 * output hardware. The autocreate option will choose the most suitable