diff --git a/web/avatars/avatar-hooks.react.js b/web/avatars/avatar-hooks.react.js
--- a/web/avatars/avatar-hooks.react.js
+++ b/web/avatars/avatar-hooks.react.js
@@ -17,7 +17,15 @@
 // TODO: flip the switch
 const useBlobServiceUploads = false;
 
-function useUploadAvatarMedia(): File => Promise<UpdateUserAvatarRequest> {
+type AvatarMediaUploadOptions = {
+  uploadMetadataToKeyserver?: boolean,
+};
+
+function useUploadAvatarMedia(
+  options: AvatarMediaUploadOptions = {},
+): File => Promise<UpdateUserAvatarRequest> {
+  const { uploadMetadataToKeyserver = true } = options;
+
   const callUploadMultimedia = useLegacyAshoatKeyserverCall(uploadMultimedia);
   const callBlobServiceUpload = useBlobServiceUpload();
   const uploadAvatarMedia = React.useCallback(
@@ -32,7 +40,9 @@
         ...dimensions,
         loop: false,
       };
-      if (!useBlobServiceUploads) {
+      const useBlobService =
+        !uploadMetadataToKeyserver || useBlobServiceUploads;
+      if (!useBlobService) {
         const { id } = await callUploadMultimedia(fixedFile, uploadExtras);
         return { type: 'image', uploadID: id };
       }
@@ -56,7 +66,7 @@
         ? thumbHashResult.thumbHash
         : null;
 
-      const { id } = await callBlobServiceUpload({
+      const { id, uri } = await callBlobServiceUpload({
         uploadInput: {
           blobInput: {
             type: 'file',
@@ -68,13 +78,24 @@
           loop: false,
           thumbHash,
         },
-        keyserverOrThreadID: authoritativeKeyserverID,
+        keyserverOrThreadID: uploadMetadataToKeyserver
+          ? authoritativeKeyserverID
+          : null,
         callbacks: {},
       });
 
-      return { type: 'encrypted_image', uploadID: id };
+      if (uploadMetadataToKeyserver) {
+        return { type: 'encrypted_image', uploadID: id };
+      }
+
+      return {
+        type: 'thick_thread_image',
+        blobURI: uri,
+        thumbHash,
+        encryptionKey,
+      };
     },
-    [callBlobServiceUpload, callUploadMultimedia],
+    [callBlobServiceUpload, callUploadMultimedia, uploadMetadataToKeyserver],
   );
   return uploadAvatarMedia;
 }
diff --git a/web/avatars/edit-thread-avatar-menu.react.js b/web/avatars/edit-thread-avatar-menu.react.js
--- a/web/avatars/edit-thread-avatar-menu.react.js
+++ b/web/avatars/edit-thread-avatar-menu.react.js
@@ -10,6 +10,7 @@
   ThreadInfo,
   RawThreadInfo,
 } from 'lib/types/minimally-encoded-thread-permissions-types.js';
+import { threadTypeIsThick } from 'lib/types/thread-types-enum.js';
 
 import { useUploadAvatarMedia } from './avatar-hooks.react.js';
 import css from './edit-avatar-menu.css';
@@ -58,7 +59,9 @@
     [],
   );
 
-  const uploadAvatarMedia = useUploadAvatarMedia();
+  const uploadAvatarMedia = useUploadAvatarMedia({
+    uploadMetadataToKeyserver: !threadTypeIsThick(threadInfo.type),
+  });
   const onImageSelected = React.useCallback(
     async (event: SyntheticEvent<HTMLInputElement>) => {
       const { target } = event;