diff --git a/crates/sidebar/src/project_group_builder.rs b/crates/sidebar/src/project_group_builder.rs
index d03190e028082e086b30956933780090c1be07e5..cfb84cd9e1b0d0e84529bb068f027539a3a87271 100644
--- a/crates/sidebar/src/project_group_builder.rs
+++ b/crates/sidebar/src/project_group_builder.rs
@@ -179,7 +179,11 @@ impl ProjectGroupBuilder {
     /// Whether the given group should load threads for a linked worktree at
     /// `worktree_path`. Returns `false` if the worktree already has an open
     /// workspace in the group (its threads are loaded via the workspace loop)
-    /// or if the worktree's canonical path list doesn't match `group_path_list`.
+    /// or if the worktree's canonical repo path isn't one of the group's roots.
+    ///
+    /// When multiple groups contain the same main repo, all of them will
+    /// return `true`. Callers must deduplicate across groups (e.g. using
+    /// `current_session_ids`) so that only the first group claims the thread.
     pub fn group_owns_worktree(
         &self,
         group: &ProjectGroup,
@@ -190,17 +194,11 @@ impl ProjectGroupBuilder {
         if group.covered_paths.contains(&worktree_arc) {
             return false;
         }
-        let canonical = self.canonicalize_path_list(&PathList::new(&[worktree_path]));
-        canonical == *group_path_list
-    }
-
-    fn canonicalize_path_list(&self, path_list: &PathList) -> PathList {
-        let paths: Vec<_> = path_list
+        let canonical = self.canonicalize_path(worktree_path);
+        group_path_list
             .paths()
             .iter()
-            .map(|p| self.canonicalize_path(p).to_path_buf())
-            .collect();
-        PathList::new(&paths)
+            .any(|p| Path::new(p) == canonical)
     }
 
     pub fn groups(&self) -> impl Iterator<Item = (&ProjectGroupName, &ProjectGroup)> {
diff --git a/crates/sidebar/src/sidebar.rs b/crates/sidebar/src/sidebar.rs
index 93d497bde90f0f8bff7dfe4ae8ec11fe1e794a29..a4739e5c64fccb5740889217a7cbc7d113413375 100644
--- a/crates/sidebar/src/sidebar.rs
+++ b/crates/sidebar/src/sidebar.rs
@@ -770,6 +770,9 @@ impl Sidebar {
                         if !seen_session_ids.insert(row.session_id.clone()) {
                             continue;
                         }
+                        if current_session_ids.contains(&row.session_id) {
+                            continue;
+                        }
                         let worktree_info = row.folder_paths.paths().first().and_then(|path| {
                             let canonical = project_groups.canonicalize_path(path);
                             if canonical != path.as_path() {
@@ -7140,17 +7143,15 @@ mod tests {
         multi_workspace.update_in(cx, |_, _window, cx| cx.notify());
         cx.run_until_parked();
 
-        // BUG: The thread appears under [project] (the individual workspace)
-        // because group_owns_worktree canonicalizes /wt-feature to /project
-        // and matches it to the [project] group. It should instead appear
-        // under [project, project-b] since that workspace owns the repo.
+        // The thread should appear under [project, project-b] because that
+        // group was created first and contains the main repo /project.
         assert_eq!(
             visible_entries_as_strings(&sidebar, cx),
             vec![
                 "v [project, project-b]",
-                "  [+ New Thread]",
-                "v [project]",
                 "  Worktree Thread {wt-feature}",
+                "v [project]",
+                "  [+ New Thread]",
             ]
         );
     }