diff --git a/components/script_bindings/codegen/codegen.py b/components/script_bindings/codegen/codegen.py
index bf609cf563b..1013e1a01fa 100644
--- a/components/script_bindings/codegen/codegen.py
+++ b/components/script_bindings/codegen/codegen.py
@@ -3213,7 +3213,8 @@ create_global_object::<D>(
     raw.as_ptr() as *const libc::c_void,
     {TRACE_HOOK_NAME}::<D>,
     obj.handle_mut(),
-    origin);
+    origin,
+    {"true" if self.descriptor.useSystemCompartment else "false"});
 assert!(!obj.is_null());
 
 let root = raw.reflect_with(obj.get());
diff --git a/components/script_bindings/codegen/configuration.py b/components/script_bindings/codegen/configuration.py
index e540b0c3101..f7ca3303927 100644
--- a/components/script_bindings/codegen/configuration.py
+++ b/components/script_bindings/codegen/configuration.py
@@ -252,6 +252,7 @@ class Descriptor(DescriptorProvider):
         self.outerObjectHook = desc.get('outerObjectHook', 'None')
         self.proxy = False
         self.weakReferenceable = desc.get('weakReferenceable', False)
+        self.useSystemCompartment = desc.get('useSystemCompartment', False)
 
         # If we're concrete, we need to crawl our ancestor interfaces and mark
         # them as having a concrete descendant.
diff --git a/components/script_bindings/interface.rs b/components/script_bindings/interface.rs
index e185cfe9cfd..bb7e27df910 100644
--- a/components/script_bindings/interface.rs
+++ b/components/script_bindings/interface.rs
@@ -17,10 +17,10 @@ use js::jsapi::{
     HandleObject as RawHandleObject, IsSharableCompartment, IsSystemCompartment,
     JS_AtomizeAndPinString, JS_GetFunctionObject, JS_GetProperty, JS_IterateCompartments,
     JS_NewFunction, JS_NewGlobalObject, JS_NewObject, JS_NewStringCopyN, JS_SetReservedSlot,
-    JS_WrapObject, JSAutoRealm, JSClass, JSClassOps, JSContext, JSFUN_CONSTRUCTOR, JSFunctionSpec,
-    JSObject, JSPROP_ENUMERATE, JSPROP_PERMANENT, JSPROP_READONLY, JSPROP_RESOLVING,
-    JSPropertySpec, JSString, JSTracer, ObjectOps, OnNewGlobalHookOption, SymbolCode,
-    TrueHandleValue, Value, jsid,
+    JS_SetTrustedPrincipals, JS_WrapObject, JSAutoRealm, JSClass, JSClassOps, JSContext,
+    JSFUN_CONSTRUCTOR, JSFunctionSpec, JSObject, JSPROP_ENUMERATE, JSPROP_PERMANENT,
+    JSPROP_READONLY, JSPROP_RESOLVING, JSPropertySpec, JSString, JSTracer, ObjectOps,
+    OnNewGlobalHookOption, SymbolCode, TrueHandleValue, Value, jsid,
 };
 use js::jsval::{JSVal, NullValue, PrivateValue};
 use js::rust::wrappers::{
@@ -142,15 +142,33 @@ pub(crate) unsafe fn create_global_object<D: DomTypes>(
     trace: TraceHook,
     mut rval: MutableHandleObject,
     origin: &MutableOrigin,
+    use_system_compartment: bool,
 ) {
     assert!(rval.is_null());
 
     let mut options = RealmOptions::default();
     options.creationOptions_.traceGlobal_ = Some(trace);
     options.creationOptions_.sharedMemoryAndAtomics_ = false;
-    select_compartment(cx, &mut options);
+    if use_system_compartment {
+        options.creationOptions_.compSpec_ = CompartmentSpecifier::NewCompartmentAndZone;
+        options.creationOptions_.__bindgen_anon_1.comp_ = std::ptr::null_mut();
+    } else {
+        select_compartment(cx, &mut options);
+    }
 
+    // “System or addon” principals control JIT policy (IsBaselineJitEnabled, IsIonEnabled) and WASM policy
+    // (IsSimdPrivilegedContext, HasSupport). This is unrelated to the concept of “system” compartments, though WASM
+    // HasSupport describes checking this flag as “check trusted principals”, which seems to be a mistake.
+    // Servo currently creates all principals as non-system-or-addon principals.
     let principal = ServoJSPrincipals::new::<D>(origin);
+    if use_system_compartment {
+        // “System” compartments are those that have all “system” realms, which in turn are those that were
+        // created with the runtime’s global “trusted” principals. This influences the IsSystemCompartment() check
+        // in select_compartment() below [1], preventing compartment reuse in either direction between this global
+        // and any globals created with `use_system_compartment` set to false.
+        // [1] IsSystemCompartment() → Realm::isSystem() → Realm::isSystem_ → principals == trustedPrincipals()
+        JS_SetTrustedPrincipals(*cx, principal.as_raw());
+    }
 
     rval.set(JS_NewGlobalObject(
         *cx,