feat(office): Preview PDF rep if using internet explorer

src/i18n/en-US.properties

@@ -88,6 +88,8 @@ error_bad_file=We’re sorry the preview didn’t load. This file could not be c
 error_not_downloadable=Oops! It looks like something is wrong with this file. We apologize for the inconvenience and recommend that you upload a new version of this file or roll back to a previous version. Please contact us for more details.
 # Preview error message shown when flash is not enabled on their browser
 error_flash_not_enabled=We’re sorry, the preview didn’t load because Flash is not enabled on your browser. If possible, please enable Flash and refresh the page.
+# Preview error message shown when loading what would be an Office Excel Online file extension in Internet Explorer
+error_internet_explorer_office_online=Microsoft 365 apps and services no longer support Internet Explorer 11, therefore, Box users may have a degraded experience.
 
 # Archive Preview
 # Label for filename column name

src/lib/Preview.js

@@ -43,6 +43,7 @@ import {
 import {
     API_HOST,
     APP_HOST,
+    BROWSERS,
     CLASS_NAVIGATION_VISIBILITY,
     ERROR_CODE_403_FORBIDDEN_BY_POLICY,
     PERMISSION_PREVIEW,
@@ -1009,6 +1010,21 @@ class Preview extends EventEmitter {
                 this.enableViewers(viewerName);
             }
         });
+
+        // Disable office online if browser is IE
+        this.forceDisableOfficeOnline();
+    }
+
+    /**
+     * Adds Office viewer to the disabled viewer list if browser is IE
+     * @returns {void}
+     */
+    forceDisableOfficeOnline() {
+        const isIE = this.browserInfo.name === BROWSERS.INTERNET_EXPLORER;
+
+        if (isIE) {
+            this.disableViewers('Office');
+        }
     }
 
     /**

src/lib/viewers/doc/DocLoader.js

@@ -2,6 +2,7 @@ import AssetLoader from '../AssetLoader';
 import { getRepresentation } from '../../file';
 import AutoCADViewer from './AutoCADViewer';
 import DocumentViewer from './DocumentViewer';
+import OfficeExcelViewer from './OfficeExcelViewer';
 import PresentationViewer from './PresentationViewer';
 import SinglePageViewer from './SinglePageViewer';
 import RepStatus from '../../RepStatus';
@@ -18,6 +19,12 @@ const VIEWERS = [
         REP: 'pdf',
         EXT: ['gslide', 'gslides', 'odp', 'ppt', 'pptx', 'key'],
     },
+    {
+        NAME: 'OfficeExcel',
+        CONSTRUCTOR: OfficeExcelViewer,
+        REP: 'pdf',
+        EXT: ['xlsx', 'xlsm', 'xlsb'],
+    },
     {
         NAME: 'AutoCAD',
         CONSTRUCTOR: AutoCADViewer,

src/lib/viewers/doc/OfficeExcelViewer.js

@@ -0,0 +1,14 @@
+import DocumentViewer from './DocumentViewer';
+
+class OfficeExcelViewer extends DocumentViewer {
+    /**
+     * @inheritdoc
+     */
+    load() {
+        super.load();
+
+        this.options.ui.showNotification(__('error_internet_explorer_office_online'), null, true);
+    }
+}
+
+export default OfficeExcelViewer;