diff --git a/src/lib/http.ts b/src/lib/http.ts
index 7d1fc5d..df86e91 100644
--- a/src/lib/http.ts
+++ b/src/lib/http.ts
@@ -127,6 +127,11 @@ export async function request(url: string, options: RequestOptions = {}): Promis
 
   let lastError: unknown
   for (let attempt = 0; ; attempt++) {
+    // AbortSignal.timeout is Chrome 103; AbortSignal.any is Chrome 116, above
+    // the manifest's minimum_chrome_version. Nothing passes `signal` today, so
+    // that branch is unreachable and the floor stays where it is — but the
+    // first caller to pass one makes 116 the real minimum. Raise
+    // minimum_chrome_version then, or combine the signals by hand here.
     const timeout = AbortSignal.timeout(timeoutMs)
     const signal = options.signal ? AbortSignal.any([options.signal, timeout]) : timeout
     // Decided rather than thrown: a `throw` here would be caught by this same