diff --git a/crates/torii/grpc/src/client.rs b/crates/torii/grpc/src/client.rs
index 4a11e04777..29c2e52b16 100644
--- a/crates/torii/grpc/src/client.rs
+++ b/crates/torii/grpc/src/client.rs
@@ -3,7 +3,7 @@ use std::num::ParseIntError;
 
 use futures_util::stream::MapOk;
 use futures_util::{Stream, StreamExt, TryStreamExt};
-use starknet::core::types::{FromStrError, StateUpdate};
+use starknet::core::types::{FromStrError, StateDiff, StateUpdate};
 use starknet_crypto::FieldElement;
 
 use crate::proto::world::{
@@ -144,9 +144,11 @@ impl WorldClient {
             .map_err(Error::Grpc)
             .map(|res| res.into_inner())?;
 
-        Ok(ModelDiffsStreaming(stream.map_ok(Box::new(|res| {
-            let update = res.model_update.expect("qed; state update must exist");
-            TryInto::<StateUpdate>::try_into(update).expect("must able to serialize")
+        Ok(ModelDiffsStreaming(stream.map_ok(Box::new(|res| match res.model_update {
+            Some(update) => {
+                TryInto::<StateUpdate>::try_into(update).expect("must able to serialize")
+            }
+            None => empty_state_update(),
         }))))
     }
 }
@@ -184,3 +186,19 @@ impl Stream for EntityUpdateStreaming {
         self.0.poll_next_unpin(cx)
     }
 }
+
+fn empty_state_update() -> StateUpdate {
+    StateUpdate {
+        block_hash: FieldElement::ZERO,
+        new_root: FieldElement::ZERO,
+        old_root: FieldElement::ZERO,
+        state_diff: StateDiff {
+            declared_classes: vec![],
+            deployed_contracts: vec![],
+            deprecated_declared_classes: vec![],
+            nonces: vec![],
+            replaced_classes: vec![],
+            storage_diffs: vec![],
+        },
+    }
+}
diff --git a/crates/torii/grpc/src/server/subscriptions/model_diff.rs b/crates/torii/grpc/src/server/subscriptions/model_diff.rs
index ad257c719c..b74b5098c4 100644
--- a/crates/torii/grpc/src/server/subscriptions/model_diff.rs
+++ b/crates/torii/grpc/src/server/subscriptions/model_diff.rs
@@ -20,6 +20,7 @@ use tracing::{debug, error, trace};
 
 use super::error::SubscriptionError;
 use crate::proto;
+use crate::proto::world::SubscribeModelsResponse;
 use crate::types::KeysClause;
 
 pub(crate) const LOG_TARGET: &str = "torii::grpc::server::subscriptions::model_diff";
@@ -87,6 +88,13 @@ impl StateDiffManager {
             .await
             .insert(id, ModelDiffSubscriber { storage_addresses, sender });
 
+        // unlock issue with firefox/safari
+        // send empty model update to unlock browsers ...
+        let subscribers = self.subscribers.write().await;
+        let _ = subscribers.get(&id).unwrap().sender.send(Ok(SubscribeModelsResponse {
+            model_update: None
+        })).await;
+
         Ok(receiver)
     }
 
diff --git a/crates/torii/server/src/proxy.rs b/crates/torii/server/src/proxy.rs
index df9f4e26f5..23539b5d49 100644
--- a/crates/torii/server/src/proxy.rs
+++ b/crates/torii/server/src/proxy.rs
@@ -17,7 +17,7 @@ use tower::ServiceBuilder;
 use tower_http::cors::{AllowOrigin, CorsLayer};
 use tracing::error;
 
-const DEFAULT_ALLOW_HEADERS: [&str; 12] = [
+const DEFAULT_ALLOW_HEADERS: [&str; 11] = [
     "accept",
     "origin",
     "content-type",
@@ -27,7 +27,6 @@ const DEFAULT_ALLOW_HEADERS: [&str; 12] = [
     "x-grpc-timeout",
     "x-user-agent",
     "connection",
-    "upgrade",
     "sec-websocket-key",
     "sec-websocket-version",
 ];