--- a/toolkit/components/url-classifier/nsUrlClassifierListManager.js
+++ b/toolkit/components/url-classifier/nsUrlClassifierListManager.js
@@ -279,17 +279,17 @@ PROT_ListManager.prototype.kickoffUpdate
       let nextUpdatePref = "browser.safebrowsing.provider." + provider +
                            ".nextupdatetime";
       let nextUpdate = Services.prefs.getCharPref(nextUpdatePref, "");
 
       if (nextUpdate) {
         updateDelay = Math.min(maxDelayMs, Math.max(0, nextUpdate - Date.now()));
         log("Next update at " + nextUpdate);
       }
-      log("Next update " + updateDelay / 60000 + "min from now");
+      log("Next update " + Math.round(updateDelay / 60000) + "min from now");
 
       this.setUpdateCheckTimer(updateUrl, updateDelay);
     } else {
       log("No updates needed or already initialized for " + updateUrl);
     }
   }
 };
 
@@ -561,24 +561,24 @@ PROT_ListManager.prototype.updateSuccess
   if (waitForUpdateSec) {
     delay = parseInt(waitForUpdateSec, 10) * 1000;
   }
   // As long as the delay is something sane (5 min to 1 day), update
   // our delay time for requesting updates. We always use a non-repeating
   // timer since the delay is set differently at every callback.
   if (delay > maxDelayMs) {
     log("Ignoring delay from server (too long), waiting " +
-        maxDelayMs / 60000 + "min");
+        Math.round(maxDelayMs / 60000) + "min");
     delay = maxDelayMs;
   } else if (delay < minDelayMs) {
     log("Ignoring delay from server (too short), waiting " +
-        this.updateInterval / 60000 + "min");
+        Math.round(this.updateInterval / 60000) + "min");
     delay = this.updateInterval;
   } else {
-    log("Waiting " + delay / 60000 + "min");
+    log("Waiting " + Math.round(delay / 60000) + "min");
   }
 
   this.setUpdateCheckTimer(updateUrl, delay);
 
   // Let the backoff object know that we completed successfully.
   this.requestBackoffs_[updateUrl].noteServerResponse(200);
 
   // Set last update time for provider
@@ -601,17 +601,17 @@ PROT_ListManager.prototype.updateSuccess
   let lastUpdatePref = "browser.safebrowsing.provider." + provider + ".lastupdatetime";
   let now = Date.now();
   log("Setting last update of " + provider + " to " + now);
   Services.prefs.setCharPref(lastUpdatePref, now.toString());
 
   let nextUpdatePref = "browser.safebrowsing.provider." + provider + ".nextupdatetime";
   let targetTime = now + delay;
   log("Setting next update of " + provider + " to " + targetTime
-      + " (" + delay / 60000 + "min from now)");
+      + " (" + Math.round(delay / 60000) + "min from now)");
   Services.prefs.setCharPref(nextUpdatePref, targetTime.toString());
 
   Services.obs.notifyObservers(null, "safebrowsing-update-finished", "success");
 };
 
 /**
  * Callback function if the update request succeeded.
  * @param result String The error code of the failure