Move operation serialization off the main thread

crates/editor/src/multi_buffer.rs

@@ -3304,7 +3304,10 @@ mod tests {
     fn test_remote_multibuffer(cx: &mut MutableAppContext) {
         let host_buffer = cx.add_model(|cx| Buffer::new(0, "a", cx));
         let guest_buffer = cx.add_model(|cx| {
-            let (state, ops) = host_buffer.read(cx).to_proto();
+            let state = host_buffer.read(cx).to_proto();
+            let ops = cx
+                .background()
+                .block(host_buffer.read(cx).serialize_ops(cx));
             let mut buffer = Buffer::from_proto(1, state, None).unwrap();
             buffer
                 .apply_ops(