Fix duplicating slide with images in OnlyOffice

www/common/onlyoffice/inner.js

@@ -1501,6 +1501,37 @@ define([
                                 APP.onDocumentUnlock = undefined;
                             }
                             break;
+                        case 'openDocument':
+                            // When duplicating a slide, OO may ask the URLs of the images
+                            // in that slide
+                            var _obj = obj.message;
+                            if (_obj.c === "imgurls") {
+                                var _mediasSources = getMediasSources();
+                                var images = _obj.data || [];
+                                if (!Array.isArray(images)) { return; }
+                                var urls = images.map(function (name) {
+                                    var data = _mediasSources[name];
+                                    if (!data) { return; }
+                                    var media = mediasData[data.src];
+                                    if (!media) { return; }
+                                    return {
+                                        path: name,
+                                        url: media.blobUrl,
+                                    };
+                                }).filter(Boolean);
+                                send({
+                                    type: "documentOpen",
+                                    data: {
+                                        type: "imgurls",
+                                        status: "ok",
+                                        data: {
+                                            urls: urls,
+                                            error: 0
+                                        }
+                                    }
+                                });
+                            }
+                            break;
                     }
                 });
             });