diff --git a/app/assets/javascripts/discourse/app/services/media-optimization-worker.js b/app/assets/javascripts/discourse/app/services/media-optimization-worker.js
index 1cac1783573..f2e82584761 100644
--- a/app/assets/javascripts/discourse/app/services/media-optimization-worker.js
+++ b/app/assets/javascripts/discourse/app/services/media-optimization-worker.js
@@ -60,7 +60,7 @@ export default class MediaOptimizationWorkerService extends Service {
       this.logIfDebug(`Transforming ${file.name}`);
 
       this.currentComposerUploadData = data;
-      this.promiseResolvers[file.name] = resolve;
+      this.promiseResolvers[this.usingUppy ? file.id : file.name] = resolve;
 
       let imageData;
       try {
@@ -77,6 +77,7 @@ export default class MediaOptimizationWorkerService extends Service {
       this.worker.postMessage(
         {
           type: "compress",
+          fileId: file.id,
           file: imageData.data.buffer,
           fileName: file.name,
           width: imageData.width,
@@ -117,7 +118,7 @@ export default class MediaOptimizationWorkerService extends Service {
     this.worker.onmessage = (e) => {
       switch (e.data.type) {
         case "file":
-          let optimizedFile = new File([e.data.file], `${e.data.fileName}`, {
+          let optimizedFile = new File([e.data.file], e.data.fileName, {
             type: "image/jpeg",
           });
           this.logIfDebug(
@@ -125,7 +126,7 @@ export default class MediaOptimizationWorkerService extends Service {
           );
 
           if (this.usingUppy) {
-            this.promiseResolvers[optimizedFile.name](optimizedFile);
+            this.promiseResolvers[e.data.fileId](optimizedFile);
           } else {
             let data = this.currentComposerUploadData;
             data.files[data.index] = optimizedFile;
@@ -143,7 +144,7 @@ export default class MediaOptimizationWorkerService extends Service {
           }
 
           if (this.usingUppy) {
-            this.promiseResolvers[e.data.fileName]();
+            this.promiseResolvers[e.data.fileId]();
           } else {
             this.promiseResolvers[e.data.fileName](
               this.currentComposerUploadData
diff --git a/public/javascripts/media-optimization-worker.js b/public/javascripts/media-optimization-worker.js
index 3ed3c52a61a..189a88b761f 100644
--- a/public/javascripts/media-optimization-worker.js
+++ b/public/javascripts/media-optimization-worker.js
@@ -131,7 +131,8 @@ onmessage = async function (e) {
           {
             type: "file",
             file: optimized,
-            fileName: e.data.fileName
+            fileName: e.data.fileName,
+            fileId: e.data.fileId
           },
           [optimized]
         );
@@ -140,7 +141,8 @@ onmessage = async function (e) {
         postMessage({
           type: "error",
           file: e.data.file,
-          fileName: e.data.fileName
+          fileName: e.data.fileName,
+          fileId: e.data.fileId
         });
       }
       break;