diff --git a/components/script/dom/readablestream.rs b/components/script/dom/readablestream.rs
index 1c6ac242e9be..90e6c72da708 100644
--- a/components/script/dom/readablestream.rs
+++ b/components/script/dom/readablestream.rs
@@ -6,7 +6,7 @@ use crate::dom::bindings::conversions::{ConversionBehavior, ConversionResult};
 use crate::dom::bindings::error::Error;
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
 use crate::dom::bindings::root::DomRoot;
-use crate::dom::bindings::settings_stack::AutoEntryScript;
+use crate::dom::bindings::settings_stack::{AutoEntryScript, AutoIncumbentScript};
 use crate::dom::bindings::utils::get_dictionary_property;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::promise::Promise;
@@ -118,6 +118,7 @@ impl ReadableStream {
         source: ExternalUnderlyingSource,
     ) -> DomRoot<ReadableStream> {
         let _ar = enter_realm(global);
+        let _ais = AutoIncumbentScript::new(global);
         let cx = global.get_cx();
 
         let source = Rc::new(ExternalUnderlyingSourceController::new(source));