diff --git a/lib/init-action-post.js b/lib/init-action-post.js
index 8b792f4b2..60311a02b 100644
--- a/lib/init-action-post.js
+++ b/lib/init-action-post.js
@@ -165564,7 +165564,7 @@ async function saveOverlayStatus(codeql, languages, diskUsage, status, logger) {
   const statusFile = path7.join(
     getTemporaryDirectory(),
     "overlay-status",
-    languages.sort().join("+"),
+    [...languages].sort().join("+"),
     STATUS_FILE_NAME
   );
   await fs6.promises.mkdir(path7.dirname(statusFile), { recursive: true });
@@ -165591,7 +165591,7 @@ async function saveOverlayStatus(codeql, languages, diskUsage, status, logger) {
 }
 async function getCacheKey(codeql, languages, diskUsage) {
   const diskSpaceToNearest10Gb = `${10 * Math.floor(diskUsage.numTotalBytes / (10 * 1024 * 1024 * 1024))}GB`;
-  return `codeql-overlay-status-${languages.sort().join("+")}-${(await codeql.getVersion()).version}-runner-${diskSpaceToNearest10Gb}`;
+  return `codeql-overlay-status-${[...languages].sort().join("+")}-${(await codeql.getVersion()).version}-runner-${diskSpaceToNearest10Gb}`;
 }
 
 // src/trap-caching.ts
diff --git a/lib/init-action.js b/lib/init-action.js
index f0bd83b85..10b9a8489 100644
--- a/lib/init-action.js
+++ b/lib/init-action.js
@@ -105730,7 +105730,7 @@ async function getOverlayStatus(codeql, languages, diskUsage, logger) {
   const statusFile = path7.join(
     getTemporaryDirectory(),
     "overlay-status",
-    languages.sort().join("+"),
+    [...languages].sort().join("+"),
     STATUS_FILE_NAME
   );
   await fs5.promises.mkdir(path7.dirname(statusFile), { recursive: true });
@@ -105763,7 +105763,7 @@ async function getOverlayStatus(codeql, languages, diskUsage, logger) {
 }
 async function getCacheKey(codeql, languages, diskUsage) {
   const diskSpaceToNearest10Gb = `${10 * Math.floor(diskUsage.numTotalBytes / (10 * 1024 * 1024 * 1024))}GB`;
-  return `codeql-overlay-status-${languages.sort().join("+")}-${(await codeql.getVersion()).version}-runner-${diskSpaceToNearest10Gb}`;
+  return `codeql-overlay-status-${[...languages].sort().join("+")}-${(await codeql.getVersion()).version}-runner-${diskSpaceToNearest10Gb}`;
 }
 
 // src/trap-caching.ts
diff --git a/src/overlay/status.ts b/src/overlay/status.ts
index 390682f1a..ca638e754 100644
--- a/src/overlay/status.ts
+++ b/src/overlay/status.ts
@@ -81,7 +81,7 @@ export async function getOverlayStatus(
   const statusFile = path.join(
     getTemporaryDirectory(),
     "overlay-status",
-    languages.sort().join("+"),
+    [...languages].sort().join("+"),
     STATUS_FILE_NAME,
   );
   await fs.promises.mkdir(path.dirname(statusFile), { recursive: true });
@@ -132,7 +132,7 @@ export async function saveOverlayStatus(
   const statusFile = path.join(
     getTemporaryDirectory(),
     "overlay-status",
-    languages.sort().join("+"),
+    [...languages].sort().join("+"),
     STATUS_FILE_NAME,
   );
   await fs.promises.mkdir(path.dirname(statusFile), { recursive: true });
@@ -174,5 +174,5 @@ export async function getCacheKey(
 
   // Include the CodeQL version in the cache key so we will try again to use overlay analysis when
   // new queries and libraries that may be more efficient are released.
-  return `codeql-overlay-status-${languages.sort().join("+")}-${(await codeql.getVersion()).version}-runner-${diskSpaceToNearest10Gb}`;
+  return `codeql-overlay-status-${[...languages].sort().join("+")}-${(await codeql.getVersion()).version}-runner-${diskSpaceToNearest10Gb}`;
 }