diff --git a/lib/shared/thread-utils.js b/lib/shared/thread-utils.js
--- a/lib/shared/thread-utils.js
+++ b/lib/shared/thread-utils.js
@@ -1411,8 +1411,8 @@
 }
 
 function checkIfDefaultMembersAreVoiced(threadInfo: ThreadInfo): boolean {
-  const defaultRoleID = Object.keys(threadInfo.roles).find(
-    roleID => threadInfo.roles[roleID].isDefault,
+  const defaultRoleID = Object.keys(threadInfo.roles).find(roleID =>
+    roleIsDefaultRole(threadInfo.roles[roleID]),
   );
   invariant(
     defaultRoleID !== undefined,
@@ -1609,7 +1609,7 @@
   if (
     canRemoveMembers &&
     !memberInfo.isViewer &&
-    (canChangeRoles || threadInfo.roles[role]?.isDefault)
+    (canChangeRoles || roleIsDefaultRole(threadInfo.roles[role]))
   ) {
     result.push('remove_user');
   }