diff --git a/kallithea/lib/page.py b/kallithea/lib/page.py
--- a/kallithea/lib/page.py
+++ b/kallithea/lib/page.py
@@ -26,7 +26,7 @@ log = logging.getLogger(__name__)
 
 class Page(_Page):
     """
-    Custom pager to match rendering style with YUI paginator emitting Bootstrap paginators
+    Custom pager emitting Bootstrap paginators
     """
 
     def __init__(self, *args, **kwargs):
diff --git a/kallithea/public/less/main.less b/kallithea/public/less/main.less
--- a/kallithea/public/less/main.less
+++ b/kallithea/public/less/main.less
@@ -20,7 +20,6 @@
 /* kallithea styles */
 @import "kallithea-variables.less";
 @import "kallithea-labels.less";
-@import "yui-ac.less";
 @import "kallithea-select2.less";
 @import "kallithea-diff.less";
 @import "style.less";
diff --git a/kallithea/public/less/style.less b/kallithea/public/less/style.less
--- a/kallithea/public/less/style.less
+++ b/kallithea/public/less/style.less
@@ -459,8 +459,7 @@ div#legend_choices {
 }
 
 #content #left #menu ul.closed,
-#content #left #menu li ul.collapsed,
-.yui-tt-shadow {
+#content #left #menu li ul.collapsed {
   display: none;
 }
 #content #left #menu ul.opened,
diff --git a/kallithea/public/less/yui-ac.less b/kallithea/public/less/yui-ac.less
deleted file mode 100644
--- a/kallithea/public/less/yui-ac.less
+++ /dev/null
@@ -1,69 +0,0 @@
-.yui-overlay,
-.yui-panel-container {
-  visibility: hidden;
-  position: absolute;
-  z-index: 2;
-}
-.ac {
-  vertical-align: top;
-}
-.ac .yui-ac {
-  position: inherit;
-  font-size: 100%;
-}
-.ac .perm_ac {
-  width: 20em;
-}
-.ac .yui-ac-input {
-  width: 100%;
-}
-.ac .yui-ac-container {
-  position: absolute;
-  top: 1.6em;
-  width: auto;
-}
-.ac .yui-ac-content {
-  position: absolute;
-  border: 1px solid gray;
-  background: #fff;
-  z-index: 9050;
-}
-.ac .yui-ac-shadow {
-  position: absolute;
-  width: 100%;
-  background: #000;
-  opacity: .10;
-  z-index: 9049;
-  margin: .3em;
-}
-.ac .yui-ac-content ul {
-  width: 100%;
-  margin: 0;
-  padding: 0;
-  z-index: 9050;
-}
-.ac .yui-ac-content li {
-  cursor: default;
-  white-space: nowrap;
-  margin: 0;
-  padding: 2px 5px;
-  height: 18px;
-  z-index: 9050;
-  display: block;
-  width: auto !important;
-}
-.ac .yui-ac-content li .ac-container-wrap {
-  width: auto;
-}
-.ac .yui-ac-content li.yui-ac-prehighlight {
-  background: #B3D4FF;
-  z-index: 9050;
-}
-.ac .yui-ac-content li.yui-ac-highlight {
-  background: #556CB5;
-  color: #FFF;
-  z-index: 9050;
-}
-.ac .yui-ac-bd {
-  z-index: 9050;
-}
diff --git a/kallithea/templates/changeset/changeset_file_comment.html b/kallithea/templates/changeset/changeset_file_comment.html
--- a/kallithea/templates/changeset/changeset_file_comment.html
+++ b/kallithea/templates/changeset/changeset_file_comment.html
@@ -85,7 +85,7 @@
         <div class="comment-help">
           <span class="text-muted">${_('Comments are in plain text. Use @username to notify another user.')|n}</span>
         </div>
-        <textarea name="text" class="form-control comment-block-ta yui-ac-input"></textarea>
+        <textarea name="text" class="form-control"></textarea>
 
         <div id="status_block_container" class="status-block general-only hidden">
                 %if c.pull_request is None:
diff --git a/scripts/whitespacecleanup.sh b/scripts/whitespacecleanup.sh
--- a/scripts/whitespacecleanup.sh
+++ b/scripts/whitespacecleanup.sh
@@ -2,7 +2,7 @@
 
 # Enforce some consistency in whitespace - just to avoid spurious whitespaces changes
 
-files=`hg mani | egrep -v '/fontello/|/email_templates/|(/lockfiles.py|^LICENSE-MERGELY.html|^docs/Makefile|^scripts/whitespacecleanup.sh|/(graph|mergely|native.history|yui.2.9)\.js|/test_dump_html_mails.ref.html|\.png|\.gif|\.ico|\.pot|\.po|\.mo|\.tar\.gz|\.diff)$'`
+files=`hg mani | egrep -v '/fontello/|/email_templates/|(/lockfiles.py|^LICENSE-MERGELY.html|^docs/Makefile|^scripts/whitespacecleanup.sh|/(graph|mergely|native.history)\.js|/test_dump_html_mails.ref.html|\.png|\.gif|\.ico|\.pot|\.po|\.mo|\.tar\.gz|\.diff)$'`
 
 sed -i "s/`printf '\r'`//g" $files
 sed -i -e "s,`printf '\t'`,    ,g" $files