diff --git a/www/common/onlyoffice/inner.js b/www/common/onlyoffice/inner.js
index 591eccc2c..195991db9 100644
--- a/www/common/onlyoffice/inner.js
+++ b/www/common/onlyoffice/inner.js
@@ -1156,6 +1156,14 @@ define([
         };
 
         var handleChanges = function (obj, send) {
+            if (APP.history) {
+                send({
+                    type: "unSaveLock",
+                    index: ooChannel.cpIndex,
+                    time: +new Date()
+                });
+                return;
+            }
             // Add a new entry to the pendingChanges object.
             // If we can't send the patch within 30s, force a page reload
             var uid = Util.uid();
diff --git a/www/common/outer/onlyoffice.js b/www/common/outer/onlyoffice.js
index b5c3e7ba1..dbde5e199 100644
--- a/www/common/outer/onlyoffice.js
+++ b/www/common/outer/onlyoffice.js
@@ -87,8 +87,10 @@ define([
             chan.wc = wc;
             chan.sendMsg = function (msg, cb) {
                 cb = cb || function () {};
+                var hash = msg.slice(0, 64);
                 wc.bcast(msg).then(function () {
                     chan.history.push(msg);
+                    chan.lastKnownHash = hash;
                     cb();
                 }, function (err) {
                     cb({error: err});