diff --git a/internal/core/window.rs b/internal/core/window.rs
index 9dce219afa9..2549d25725e 100644
--- a/internal/core/window.rs
+++ b/internal/core/window.rs
@@ -25,11 +25,12 @@ use crate::renderer::Renderer;
 use crate::{Callback, Coord, SharedString};
 #[cfg(not(feature = "std"))]
 use alloc::boxed::Box;
+use alloc::collections::BTreeMap;
 use alloc::rc::{Rc, Weak};
+use alloc::vec::Vec;
 use core::cell::{Cell, RefCell};
 use core::iter;
 use core::pin::Pin;
-use std::collections::HashMap;
 use euclid::num::Zero;
 use vtable::VRcMapped;
 
@@ -433,7 +434,7 @@ pub struct WindowInner {
     maximized: Cell<bool>,
     minimized: Cell<bool>,
 
-    active_popups: RefCell<HashMap<u32, PopupWindow>>,
+    active_popups: RefCell<BTreeMap<u32, PopupWindow>>,
     popup_counter: Cell<u32>,
     close_requested: Callback<(), CloseRequestResponse>,
     click_state: ClickState,