diff --git a/src/view/control/AphrontCursorPagerView.php b/src/view/control/AphrontCursorPagerView.php
index 4608158481..cdb9562624 100644
--- a/src/view/control/AphrontCursorPagerView.php
+++ b/src/view/control/AphrontCursorPagerView.php
@@ -1,189 +1,189 @@
 <?php
 
 final class AphrontCursorPagerView extends AphrontView {
 
   private $afterID;
   private $beforeID;
 
   private $pageSize = 100;
 
   private $nextPageID;
   private $prevPageID;
   private $moreResults;
 
   private $uri;
 
   public function setPageSize($page_size) {
     $this->pageSize = max(1, $page_size);
     return $this;
   }
 
   public function getPageSize() {
     return $this->pageSize;
   }
 
   public function setURI(PhutilURI $uri) {
     $this->uri = $uri;
     return $this;
   }
 
   public function readFromRequest(AphrontRequest $request) {
     $this->uri = $request->getRequestURI();
     $this->afterID = $request->getStr('after');
     $this->beforeID = $request->getStr('before');
     return $this;
   }
 
   public function setAfterID($after_id) {
     $this->afterID = $after_id;
     return $this;
   }
 
   public function getAfterID() {
     return $this->afterID;
   }
 
   public function setBeforeID($before_id) {
     $this->beforeID = $before_id;
     return $this;
   }
 
   public function getBeforeID() {
     return $this->beforeID;
   }
 
   public function setNextPageID($next_page_id) {
     $this->nextPageID = $next_page_id;
     return $this;
   }
 
   public function getNextPageID() {
     return $this->nextPageID;
   }
 
   public function setPrevPageID($prev_page_id) {
     $this->prevPageID = $prev_page_id;
     return $this;
   }
 
   public function getPrevPageID() {
     return $this->prevPageID;
   }
 
   public function sliceResults(array $results) {
     if (count($results) > $this->getPageSize()) {
       $offset = ($this->beforeID ? count($results) - $this->getPageSize() : 0);
       $results = array_slice($results, $offset, $this->getPageSize(), true);
       $this->moreResults = true;
     }
     return $results;
   }
 
   public function getHasMoreResults() {
     return $this->moreResults;
   }
 
   public function willShowPagingControls() {
     return $this->prevPageID ||
            $this->nextPageID ||
            $this->afterID ||
            ($this->beforeID && $this->moreResults);
   }
 
   public function getFirstPageURI() {
     if (!$this->uri) {
       throw new PhutilInvalidStateException('setURI');
     }
 
     if (!$this->afterID && !($this->beforeID && $this->moreResults)) {
       return null;
     }
 
-    return $this->uri
-      ->alter('before', null)
-      ->alter('after', null);
+    return id(clone $this->uri)
+      ->removeQueryParam('after')
+      ->removeQueryParam('before');
   }
 
   public function getPrevPageURI() {
     if (!$this->uri) {
       throw new PhutilInvalidStateException('getPrevPageURI');
     }
 
     if (!$this->prevPageID) {
       return null;
     }
 
-    return $this->uri
-      ->alter('after', null)
-      ->alter('before', $this->prevPageID);
+    return id(clone $this->uri)
+      ->removeQueryParam('after')
+      ->replaceQueryParam('before', $this->prevPageID);
   }
 
   public function getNextPageURI() {
     if (!$this->uri) {
       throw new PhutilInvalidStateException('setURI');
     }
 
     if (!$this->nextPageID) {
       return null;
     }
 
-    return $this->uri
-      ->alter('after', $this->nextPageID)
-      ->alter('before', null);
+    return id(clone $this->uri)
+      ->replaceQueryParam('after', $this->nextPageID)
+      ->removeQueryParam('before');
   }
 
   public function render() {
     if (!$this->uri) {
       throw new PhutilInvalidStateException('setURI');
     }
 
     $links = array();
 
     $first_uri = $this->getFirstPageURI();
     if ($first_uri) {
       $icon = id(new PHUIIconView())
         ->setIcon('fa-fast-backward');
       $links[] = id(new PHUIButtonView())
         ->setTag('a')
         ->setHref($first_uri)
         ->setIcon($icon)
         ->addClass('mml')
         ->setColor(PHUIButtonView::GREY)
         ->setText(pht('First'));
     }
 
     $prev_uri = $this->getPrevPageURI();
     if ($prev_uri) {
       $icon = id(new PHUIIconView())
         ->setIcon('fa-backward');
       $links[] = id(new PHUIButtonView())
         ->setTag('a')
         ->setHref($prev_uri)
         ->setIcon($icon)
         ->addClass('mml')
         ->setColor(PHUIButtonView::GREY)
         ->setText(pht('Prev'));
     }
 
     $next_uri = $this->getNextPageURI();
     if ($next_uri) {
       $icon = id(new PHUIIconView())
         ->setIcon('fa-forward');
       $links[] = id(new PHUIButtonView())
         ->setTag('a')
         ->setHref($next_uri)
         ->setIcon($icon, false)
         ->addClass('mml')
         ->setColor(PHUIButtonView::GREY)
         ->setText(pht('Next'));
     }
 
     return phutil_tag(
       'div',
       array(
         'class' => 'phui-pager-view',
       ),
       $links);
   }
 
 }