diff --git a/app-proto/full-interface/src/assembly.rs b/app-proto/full-interface/src/assembly.rs
index 0660d0e..c0c9959 100644
--- a/app-proto/full-interface/src/assembly.rs
+++ b/app-proto/full-interface/src/assembly.rs
@@ -49,7 +49,7 @@ impl Assembly {
     }
     
     pub fn try_insert_element(&self, elt: Element) -> bool {
-        let can_insert = self.elements_by_id.with(
+        let can_insert = self.elements_by_id.with_untracked(
             |elts_by_id| !elts_by_id.contains_key(&elt.id)
         );
         if can_insert {
@@ -62,7 +62,7 @@ impl Assembly {
         // find the next unused identifier in the default sequence
         let mut id_num = 1;
         let mut id = format!("sphere{}", id_num);
-        while self.elements_by_id.with(
+        while self.elements_by_id.with_untracked(
             |elts_by_id| elts_by_id.contains_key(&id)
         ) {
             id_num += 1;