diff --git a/crates/gpui2/src/platform/mac/display_linker.rs b/crates/gpui2/src/platform/mac/display_linker.rs
index b63cf24e26..d8f5a675a5 100644
--- a/crates/gpui2/src/platform/mac/display_linker.rs
+++ b/crates/gpui2/src/platform/mac/display_linker.rs
@@ -7,6 +7,7 @@ use std::{
 use crate::DisplayId;
 use collections::HashMap;
 use parking_lot::Mutex;
+pub use sys::CVSMPTETime as SmtpeTime;
 pub use sys::CVTimeStamp as VideoTimestamp;
 
 pub(crate) struct MacDisplayLinker {
@@ -153,7 +154,7 @@ mod sys {
         kCVTimeStampTopField | kCVTimeStampBottomField;
 
     #[repr(C)]
-    #[derive(Clone, Copy)]
+    #[derive(Clone, Copy, Default)]
     pub struct CVSMPTETime {
         pub subframes: i16,
         pub subframe_divisor: i16,
diff --git a/crates/gpui2/src/platform/test/platform.rs b/crates/gpui2/src/platform/test/platform.rs
index fa4b6e18c5..2cbc228c72 100644
--- a/crates/gpui2/src/platform/test/platform.rs
+++ b/crates/gpui2/src/platform/test/platform.rs
@@ -147,18 +147,25 @@ impl Platform for TestPlatform {
     fn set_display_link_output_callback(
         &self,
         _display_id: DisplayId,
-        _callback: Box<dyn FnMut(&crate::VideoTimestamp, &crate::VideoTimestamp) + Send>,
+        mut callback: Box<dyn FnMut(&crate::VideoTimestamp, &crate::VideoTimestamp) + Send>,
     ) {
-        unimplemented!()
+        let timestamp = crate::VideoTimestamp {
+            version: 0,
+            video_time_scale: 0,
+            video_time: 0,
+            host_time: 0,
+            rate_scalar: 0.0,
+            video_refresh_period: 0,
+            smpte_time: crate::SmtpeTime::default(),
+            flags: 0,
+            reserved: 0,
+        };
+        callback(&timestamp, &timestamp)
     }
 
-    fn start_display_link(&self, _display_id: DisplayId) {
-        unimplemented!()
-    }
+    fn start_display_link(&self, _display_id: DisplayId) {}
 
-    fn stop_display_link(&self, _display_id: DisplayId) {
-        unimplemented!()
-    }
+    fn stop_display_link(&self, _display_id: DisplayId) {}
 
     fn open_url(&self, _url: &str) {
         unimplemented!()