diff --git a/qutebrowser/models/basecompletion.py b/qutebrowser/models/basecompletion.py
index c020d4d40..728afb1af 100644
--- a/qutebrowser/models/basecompletion.py
+++ b/qutebrowser/models/basecompletion.py
@@ -29,8 +29,7 @@ from PyQt5.QtGui import QStandardItemModel, QStandardItem
 from qutebrowser.utils import usertypes, qtutils
 
 
-Role = usertypes.enum('Role', ['marks', 'sort'], start=Qt.UserRole,
-                      is_int=True)
+Role = usertypes.enum('Role', ['sort'], start=Qt.UserRole, is_int=True)
 
 
 class BaseCompletionModel(QStandardItemModel):
@@ -45,44 +44,6 @@ class BaseCompletionModel(QStandardItemModel):
         super().__init__(parent)
         self.setColumnCount(3)
 
-    def _get_marks(self, needle, haystack):
-        """Return the marks for needle in haystack.
-
-        Args:
-            needle: The substring which should match.
-            haystack: The string where the matches should be in.
-
-        Return:
-            A list of (startidx, endidx) tuples.
-        """
-        pos1 = pos2 = 0
-        marks = []
-        if not needle:
-            return marks
-        needle = needle.casefold()
-        haystack = haystack.casefold()
-        while True:
-            pos1 = haystack.find(needle, pos2)
-            if pos1 == -1:
-                break
-            pos2 = pos1 + len(needle)
-            marks.append((pos1, pos2))
-        return marks
-
-    def mark_item(self, index, needle):
-        """Mark a string in the givem item.
-
-        Args:
-            index: A QModelIndex of the item to mark.
-            needle: The string to mark.
-        """
-        qtutils.ensure_valid(index)
-        haystack = self.data(index)
-        marks = self._get_marks(needle, haystack)
-        ok = self.setData(index, marks, Role.marks)
-        if not ok:
-            raise ValueError("Error while setting data!")
-
     def new_category(self, name, sort=None):
         """Add a new category to the model.
 
diff --git a/qutebrowser/models/completionfilter.py b/qutebrowser/models/completionfilter.py
index fd9603f64..8243c2752 100644
--- a/qutebrowser/models/completionfilter.py
+++ b/qutebrowser/models/completionfilter.py
@@ -100,20 +100,6 @@ class CompletionFilterModel(QSortFilterProxyModel):
                 return index
         return QModelIndex()
 
-    def mark_all_items(self, text):
-        """Mark the given text in all visible items."""
-        if not text:
-            return
-        for i in range(self.rowCount()):
-            cat = self.index(i, 0)
-            qtutils.ensure_valid(cat)
-            for k in range(self.rowCount(cat)):
-                index = self.index(k, 0, cat)
-                qtutils.ensure_valid(index)
-                index = self.mapToSource(index)
-                qtutils.ensure_valid(index)
-                self.srcmodel.mark_item(index, text)
-
     def setSourceModel(self, model):
         """Override QSortFilterProxyModel's setSourceModel to clear pattern."""
         log.completion.debug("Setting source model: {}".format(model))
diff --git a/qutebrowser/utils/completer.py b/qutebrowser/utils/completer.py
index 90fbf2c08..d6ef33d37 100644
--- a/qutebrowser/utils/completer.py
+++ b/qutebrowser/utils/completer.py
@@ -253,6 +253,5 @@ class Completer(QObject):
             completion.hide()
             return
 
-        self._model().mark_all_items(pattern)
         if completion.enabled:
             completion.show()
diff --git a/qutebrowser/widgets/completion.py b/qutebrowser/widgets/completion.py
index 2b03a2ba2..78b96ef8d 100644
--- a/qutebrowser/widgets/completion.py
+++ b/qutebrowser/widgets/completion.py
@@ -39,8 +39,6 @@ class CompletionView(QTreeView):
     Based on QTreeView but heavily customized so root elements show as category
     headers, and children show as flat list.
 
-    Highlights completions based on marks in the Role.marks data.
-
     Class attributes:
         COLUMN_WIDTHS: A list of column widths, in percent.
 
diff --git a/qutebrowser/widgets/completiondelegate.py b/qutebrowser/widgets/completiondelegate.py
index 025d58afc..05cda5d88 100644
--- a/qutebrowser/widgets/completiondelegate.py
+++ b/qutebrowser/widgets/completiondelegate.py
@@ -184,10 +184,6 @@ class CompletionItemDelegate(QStyledItemDelegate):
             self._opt.direction, self._opt.displayAlignment))
 
         self._doc = QTextDocument(self)
-        if index.parent().isValid():
-            self._doc.setPlainText(self._opt.text)
-        else:
-            self._doc.setHtml('<b>{}</b>'.format(html.escape(self._opt.text)))
         self._doc.setDefaultFont(self._opt.font)
         self._doc.setDefaultTextOption(text_option)
         self._doc.setDefaultStyleSheet(style.get_stylesheet("""
@@ -197,21 +193,17 @@ class CompletionItemDelegate(QStyledItemDelegate):
         """))
         self._doc.setDocumentMargin(2)
 
-        if index.column() == 0 and index.model().pattern:
-            # We take a shortcut here by not checking anything if the models
-            # pattern is empty. This is required because the marks data is
-            # invalid in that case (for performance reasons).
-            marks = index.data(basecompletion.Role.marks)
-            if marks is None:
-                return
-            for mark in marks:
-                cur = QTextCursor(self._doc)
-                cur.setPosition(mark[0])
-                cur.setPosition(mark[1], QTextCursor.KeepAnchor)
-                txt = cur.selectedText()
-                cur.removeSelectedText()
-                cur.insertHtml('<span class="highlight">{}</span>'.format(
-                    html.escape(txt)))
+        if index.parent().isValid():
+            pattern = index.model().pattern
+            if index.column() == 0 and pattern:
+                text = self._opt.text.replace(
+                    pattern,
+                    '<span class="highlight">{}</span>'.format(pattern))
+                self._doc.setHtml(text)
+            else:
+                self._doc.setPlainText(self._opt.text)
+        else:
+            self._doc.setHtml('<b>{}</b>'.format(html.escape(self._opt.text)))
 
     def _draw_focus_rect(self):
         """Draw the focus rectangle of an ItemViewItem."""