It's the default already

web/apps/photos/src/components/Upload/UploadProgress.tsx

@@ -555,11 +555,11 @@ const DoneFooter: React.FC = () => {
             {uploadPhase == "done" &&
                 (finishedUploads?.get(UPLOAD_RESULT.FAILED)?.length > 0 ||
                 finishedUploads?.get(UPLOAD_RESULT.BLOCKED)?.length > 0 ? (
-                    <Button variant="contained" fullWidth onClick={retryFailed}>
+                    <Button fullWidth onClick={retryFailed}>
                         {t("RETRY_FAILED")}
                     </Button>
                 ) : (
-                    <Button variant="contained" fullWidth onClick={onClose}>
+                    <Button fullWidth onClick={onClose}>
                         {t("close")}
                     </Button>
                 ))}

web/packages/shared/themes/components.ts

@@ -108,6 +108,7 @@ export const getComponents = (
 
     MuiButton: {
         defaultProps: {
+            // Change the default button variant from "text" to "contained".
             variant: "contained",
         },
         styleOverrides: {