diff --git a/src/asynctask.js b/src/asynctask.js
index 57715d8d8..c99a22c65 100644
--- a/src/asynctask.js
+++ b/src/asynctask.js
@@ -19,9 +19,9 @@ class AsyncTask extends EventEmitter {
         // subclasses implement this
     }
 
-    async start() {
+    async start() { // should not throw!
         debug(`start: ${this.name} started`);
-        const [error] = await safe(this._run(this.#abortController.signal)); // background
+        const [error] = await safe(this._run(this.#abortController.signal));
         debug(`start: ${this.name} finished`);
         this.emit('done', { errorMessage: error?.message || '' });
         this.#abortController = null;
diff --git a/src/routes/system.js b/src/routes/system.js
index 6f26b934e..a1b643637 100644
--- a/src/routes/system.js
+++ b/src/routes/system.js
@@ -197,5 +197,5 @@ async function getFilesystemUsage(req, res, next) {
         res.end();
     });
 
-    task.start();
+    task.start(); // background
 }