diff --git a/app/javascript/flavours/glitch/actions/compose.js b/app/javascript/flavours/glitch/actions/compose.js
index 728bcf79b2..15476fc590 100644
--- a/app/javascript/flavours/glitch/actions/compose.js
+++ b/app/javascript/flavours/glitch/actions/compose.js
@@ -27,11 +27,13 @@ export const COMPOSE_REPLY_CANCEL    = 'COMPOSE_REPLY_CANCEL';
 export const COMPOSE_DIRECT          = 'COMPOSE_DIRECT';
 export const COMPOSE_MENTION         = 'COMPOSE_MENTION';
 export const COMPOSE_RESET           = 'COMPOSE_RESET';
-export const COMPOSE_UPLOAD_REQUEST  = 'COMPOSE_UPLOAD_REQUEST';
-export const COMPOSE_UPLOAD_SUCCESS  = 'COMPOSE_UPLOAD_SUCCESS';
-export const COMPOSE_UPLOAD_FAIL     = 'COMPOSE_UPLOAD_FAIL';
-export const COMPOSE_UPLOAD_PROGRESS = 'COMPOSE_UPLOAD_PROGRESS';
-export const COMPOSE_UPLOAD_UNDO     = 'COMPOSE_UPLOAD_UNDO';
+
+export const COMPOSE_UPLOAD_REQUEST    = 'COMPOSE_UPLOAD_REQUEST';
+export const COMPOSE_UPLOAD_SUCCESS    = 'COMPOSE_UPLOAD_SUCCESS';
+export const COMPOSE_UPLOAD_FAIL       = 'COMPOSE_UPLOAD_FAIL';
+export const COMPOSE_UPLOAD_PROGRESS   = 'COMPOSE_UPLOAD_PROGRESS';
+export const COMPOSE_UPLOAD_PROCESSING = 'COMPOSE_UPLOAD_PROCESSING';
+export const COMPOSE_UPLOAD_UNDO       = 'COMPOSE_UPLOAD_UNDO';
 
 export const THUMBNAIL_UPLOAD_REQUEST  = 'THUMBNAIL_UPLOAD_REQUEST';
 export const THUMBNAIL_UPLOAD_SUCCESS  = 'THUMBNAIL_UPLOAD_SUCCESS';
@@ -307,13 +309,16 @@ export function uploadCompose(files) {
           if (status === 200) {
             dispatch(uploadComposeSuccess(data, f));
           } else if (status === 202) {
+            dispatch(uploadComposeProcessing());
+
             let tryCount = 1;
+
             const poll = () => {
               api(getState).get(`/api/v1/media/${data.id}`).then(response => {
                 if (response.status === 200) {
                   dispatch(uploadComposeSuccess(response.data, f));
                 } else if (response.status === 206) {
-                  let retryAfter = (Math.log2(tryCount) || 1) * 1000;
+                  const retryAfter = (Math.log2(tryCount) || 1) * 1000;
                   tryCount += 1;
                   setTimeout(() => poll(), retryAfter);
                 }
@@ -328,6 +333,10 @@ export function uploadCompose(files) {
   };
 };
 
+export const uploadComposeProcessing = () => ({
+  type: COMPOSE_UPLOAD_PROCESSING,
+});
+
 export const uploadThumbnail = (id, file) => (dispatch, getState) => {
   dispatch(uploadThumbnailRequest());
 
diff --git a/app/javascript/flavours/glitch/features/compose/components/upload_form.js b/app/javascript/flavours/glitch/features/compose/components/upload_form.js
index 43039c674b..35880ddccc 100644
--- a/app/javascript/flavours/glitch/features/compose/components/upload_form.js
+++ b/app/javascript/flavours/glitch/features/compose/components/upload_form.js
@@ -4,7 +4,6 @@ import UploadProgressContainer from '../containers/upload_progress_container';
 import ImmutablePureComponent from 'react-immutable-pure-component';
 import UploadContainer from '../containers/upload_container';
 import SensitiveButtonContainer from '../containers/sensitive_button_container';
-import { FormattedMessage } from 'react-intl';
 
 export default class UploadForm extends ImmutablePureComponent {
   static propTypes = {
@@ -16,7 +15,7 @@ export default class UploadForm extends ImmutablePureComponent {
 
     return (
       <div className='composer--upload_form'>
-        <UploadProgressContainer icon='upload' message={<FormattedMessage id='upload_progress.label' defaultMessage='Uploading…' />} />
+        <UploadProgressContainer />
 
         {mediaIds.size > 0 && (
           <div className='content'>
diff --git a/app/javascript/flavours/glitch/features/compose/components/upload_progress.js b/app/javascript/flavours/glitch/features/compose/components/upload_progress.js
index 8896bbffd6..c7c33c418e 100644
--- a/app/javascript/flavours/glitch/features/compose/components/upload_progress.js
+++ b/app/javascript/flavours/glitch/features/compose/components/upload_progress.js
@@ -3,26 +3,34 @@ import PropTypes from 'prop-types';
 import Motion from '../../ui/util/optional_motion';
 import spring from 'react-motion/lib/spring';
 import Icon from 'flavours/glitch/components/icon';
+import { FormattedMessage } from 'react-intl';
 
 export default class UploadProgress extends React.PureComponent {
 
   static propTypes = {
     active: PropTypes.bool,
     progress: PropTypes.number,
-    icon: PropTypes.string.isRequired,
-    message: PropTypes.node.isRequired,
+    isProcessing: PropTypes.bool,
   };
 
   render () {
-    const { active, progress, icon, message } = this.props;
+    const { active, progress, isProcessing } = this.props;
 
     if (!active) {
       return null;
     }
 
+    let message;
+
+    if (isProcessing) {
+      message = <FormattedMessage id='upload_progress.processing' defaultMessage='Processing…' />;
+    } else {
+      message = <FormattedMessage id='upload_progress.label' defaultMessage='Uploading…' />;
+    }
+
     return (
       <div className='composer--upload_form--progress'>
-        <Icon id={icon} />
+        <Icon id='upload' />
 
         <div className='message'>
           {message}
diff --git a/app/javascript/flavours/glitch/features/compose/containers/upload_progress_container.js b/app/javascript/flavours/glitch/features/compose/containers/upload_progress_container.js
index 0cfee96daa..b18c76a43f 100644
--- a/app/javascript/flavours/glitch/features/compose/containers/upload_progress_container.js
+++ b/app/javascript/flavours/glitch/features/compose/containers/upload_progress_container.js
@@ -4,6 +4,7 @@ import UploadProgress from '../components/upload_progress';
 const mapStateToProps = state => ({
   active: state.getIn(['compose', 'is_uploading']),
   progress: state.getIn(['compose', 'progress']),
+  isProcessing: state.getIn(['compose', 'is_processing']),
 });
 
 export default connect(mapStateToProps)(UploadProgress);
diff --git a/app/javascript/flavours/glitch/reducers/compose.js b/app/javascript/flavours/glitch/reducers/compose.js
index 035e9f5643..b739456da5 100644
--- a/app/javascript/flavours/glitch/reducers/compose.js
+++ b/app/javascript/flavours/glitch/reducers/compose.js
@@ -15,6 +15,7 @@ import {
   COMPOSE_UPLOAD_FAIL,
   COMPOSE_UPLOAD_UNDO,
   COMPOSE_UPLOAD_PROGRESS,
+  COMPOSE_UPLOAD_PROCESSING,
   THUMBNAIL_UPLOAD_REQUEST,
   THUMBNAIL_UPLOAD_SUCCESS,
   THUMBNAIL_UPLOAD_FAIL,
@@ -223,6 +224,7 @@ function appendMedia(state, media, file) {
     }
     map.update('media_attachments', list => list.push(media));
     map.set('is_uploading', false);
+    map.set('is_processing', false);
     map.set('resetFileKey', Math.floor((Math.random() * 0x10000)));
     map.set('idempotencyKey', uuid());
     map.update('pending_media_attachments', n => n - 1);
@@ -465,10 +467,12 @@ export default function compose(state = initialState, action) {
     return state.set('is_changing_upload', false);
   case COMPOSE_UPLOAD_REQUEST:
     return state.set('is_uploading', true).update('pending_media_attachments', n => n + 1);
+  case COMPOSE_UPLOAD_PROCESSING:
+    return state.set('is_processing', true);
   case COMPOSE_UPLOAD_SUCCESS:
     return appendMedia(state, fromJS(action.media), action.file);
   case COMPOSE_UPLOAD_FAIL:
-    return state.set('is_uploading', false).update('pending_media_attachments', n => n - 1);
+    return state.set('is_uploading', false).set('is_processing', false).update('pending_media_attachments', n => n - 1);
   case COMPOSE_UPLOAD_UNDO:
     return removeMedia(state, action.media_id);
   case COMPOSE_UPLOAD_PROGRESS: