--- a/browser/components/extensions/ext-history.js
+++ b/browser/components/extensions/ext-history.js
@@ -19,17 +19,17 @@ const {
  *
  * https://developer.mozilla.org/en-US/docs/XPCOM_Interface_Reference/nsINavHistoryResultNode
  */
 function convertNavHistoryResultNode(node) {
   return {
     id: node.pageGuid,
     url: node.uri,
     title: node.title,
-    lastVisitTime: PlacesUtils.toTime(node.time),
+    lastVisitTime: PlacesUtils.toDate(node.time).getTime(),
     visitCount: node.accessCount,
   };
 }
 
 /*
  * Converts a nsINavHistoryContainerResultNode into an array of objects
  *
  * https://developer.mozilla.org/en-US/docs/XPCOM_Interface_Reference/nsINavHistoryContainerResultNode

--- a/browser/components/extensions/test/browser/browser_ext_history.js
+++ b/browser/components/extensions/test/browser/browser_ext_history.js
@@ -66,30 +66,30 @@ add_task(function* test_delete() {
   let testUrl = visits[6].uri.spec;
   ok(yield PlacesTestUtils.isPageInDB(testUrl), "expected url found in history database");
 
   extension.sendMessage("delete-url", testUrl);
   yield extension.awaitMessage("url-deleted");
   is(yield PlacesTestUtils.isPageInDB(testUrl), false, "expected url not found in history database");
 
   let filter = {
-    startTime: PlacesUtils.toTime(visits[1].visitDate),
-    endTime: PlacesUtils.toTime(visits[3].visitDate),
+    startTime: PlacesUtils.toDate(visits[1].visitDate).valueOf(),
+    endTime: PlacesUtils.toDate(visits[3].visitDate).valueOf(),
   };
 
   extension.sendMessage("delete-range", filter);
   yield extension.awaitMessage("range-deleted");
 
   ok(yield PlacesTestUtils.isPageInDB(visits[0].uri), "expected uri found in history database");
   is(yield PlacesTestUtils.visitsInDB(visits[0].uri), 2, "2 visits for uri found in history database");
   ok(yield PlacesTestUtils.isPageInDB(visits[5].uri), "expected uri found in history database");
   is(yield PlacesTestUtils.visitsInDB(visits[5].uri), 1, "1 visit for uri found in history database");
 
-  filter.startTime = PlacesUtils.toTime(visits[0].visitDate);
-  filter.endTime = PlacesUtils.toTime(visits[5].visitDate);
+  filter.startTime = PlacesUtils.toDate(visits[0].visitDate).valueOf();
+  filter.endTime = PlacesUtils.toDate(visits[5].visitDate).valueOf();
 
   extension.sendMessage("delete-range", filter);
   yield extension.awaitMessage("range-deleted");
 
   is(yield PlacesTestUtils.isPageInDB(visits[0].uri), false, "expected uri not found in history database");
   is(yield PlacesTestUtils.visitsInDB(visits[0].uri), 0, "0 visits for uri found in history database");
   is(yield PlacesTestUtils.isPageInDB(visits[5].uri), false, "expected uri not found in history database");
   is(yield PlacesTestUtils.visitsInDB(visits[5].uri), 0, "0 visits for uri found in history database");

--- a/toolkit/components/places/PlacesUtils.jsm
+++ b/toolkit/components/places/PlacesUtils.jsm
@@ -267,25 +267,24 @@ this.PlacesUtils = {
    *        the Date object to convert.
    * @return microseconds from the epoch.
    */
   toPRTime(date) {
     return date * 1000;
   },
 
   /**
-   * Convert a PRTime to a time.
+   * Convert a PRTime to a Date object.
    *
    * @param time
    *        microseconds from the epoch.
-   * @return time
-   *        milliseconds from the epoch.
+   * @return a Date object.
    */
-  toTime(time) {
-    return time / 1000;
+  toDate(time) {
+    return new Date(parseInt(time / 1000));
   },
 
   /**
    * Wraps a string in a nsISupportsString wrapper.
    * @param   aString
    *          The string to wrap.
    * @returns A nsISupportsString object containing a string.
    */