diff --git a/resources/compiled_coffeescript.zip b/resources/compiled_coffeescript.zip
index 65c3b78952..bd1e285820 100644
Binary files a/resources/compiled_coffeescript.zip and b/resources/compiled_coffeescript.zip differ
diff --git a/src/calibre/ebooks/oeb/polish/preview.coffee b/src/calibre/ebooks/oeb/polish/preview.coffee
index 8792ae891a..3dafdedd71 100644
--- a/src/calibre/ebooks/oeb/polish/preview.coffee
+++ b/src/calibre/ebooks/oeb/polish/preview.coffee
@@ -174,7 +174,7 @@ get_style_properties = (style, all_properties, node_style, is_ancestor) ->
 
 process_rules = (node, cssRules, address, sheet, sheet_index, matching_selectors, all_properties, node_style, is_ancestor, ans) ->
     for rule, rule_index in cssRules
-        rule_address = address + [rule_index]
+        rule_address = address.concat([rule_index])
         if rule.type == CSSRule.MEDIA_RULE
             process_rules(node, rule.cssRules, rule_address, sheet, sheet_index, matching_selectors, all_properties, node_style, is_ancestor, ans)
             continue
diff --git a/src/calibre/gui2/tweak_book/boss.py b/src/calibre/gui2/tweak_book/boss.py
index 3e352fb0e0..78885afd9f 100644
--- a/src/calibre/gui2/tweak_book/boss.py
+++ b/src/calibre/gui2/tweak_book/boss.py
@@ -118,6 +118,7 @@ class Boss(QObject):
         self.gui.spell_check.refresh_requested.connect(self.commit_all_editors_to_container)
         self.gui.spell_check.word_replaced.connect(self.word_replaced)
         self.gui.spell_check.word_ignored.connect(self.word_ignored)
+        self.gui.live_css.goto_declaration.connect(self.goto_style_declaration)
 
     def preferences(self):
         p = Preferences(self.gui)
@@ -1037,6 +1038,11 @@ class Boss(QObject):
             if name is not None and getattr(ed, 'syntax', None) == 'html':
                 self.gui.live_css.sync_to_editor(name)
 
+    def goto_style_declaration(self, data):
+        name = data['name']
+        editor = self.edit_file(name, syntax=data['syntax'])
+        self.gui.live_css.navigate_to_declaration(data, editor)
+
     def init_editor(self, name, editor, data=None, use_template=False):
         editor.undo_redo_state_changed.connect(self.editor_undo_redo_state_changed)
         editor.data_changed.connect(self.editor_data_changed)
diff --git a/src/calibre/gui2/tweak_book/live_css.py b/src/calibre/gui2/tweak_book/live_css.py
index 08eadd045c..f72d98d4e1 100644
--- a/src/calibre/gui2/tweak_book/live_css.py
+++ b/src/calibre/gui2/tweak_book/live_css.py
@@ -112,6 +112,8 @@ class Cell(object):  # {{{
 
 class Declaration(QWidget):
 
+    hyperlink_activated = pyqtSignal(object)
+
     def __init__(self, html_name, data, is_first=False, parent=None):
         QWidget.__init__(self, parent)
         self.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Minimum)
@@ -197,6 +199,27 @@ class Declaration(QWidget):
             self.setCursor(cursor)
         return QWidget.mouseMoveEvent(self, ev)
 
+    def mousePressEvent(self, ev):
+        if hasattr(self, 'hyperlink_rect'):
+            pos = ev.pos()
+            if self.hyperlink_rect.contains(pos):
+                self.emit_hyperlink_activated()
+        return QWidget.mouseMoveEvent(self, ev)
+
+    def emit_hyperlink_activated(self):
+        dt = self.data['type']
+        data = {'type':dt, 'name':self.html_name, 'syntax':'html'}
+        if dt == 'inline':  # style attribute
+            data['sourceline_address'] = self.data['href']
+        elif dt == 'elem':  # <style> tag
+            data['sourceline_address'] = self.data['href']
+            data['rule_address'] = self.data['rule_address']
+        else:  # stylesheet
+            data['name'] = self.data['href']
+            data['rule_address'] = self.data['rule_address']
+            data['syntax'] = 'css'
+        self.hyperlink_activated.emit(data)
+
     def leaveEvent(self, ev):
         self.update_hover(False)
         self.setCursor(Qt.ArrowCursor)
@@ -211,6 +234,8 @@ class Declaration(QWidget):
 
 class Box(QWidget):
 
+    hyperlink_activated = pyqtSignal(object)
+
     def __init__(self, parent=None):
         QWidget.__init__(self, parent)
         self.l = l = QVBoxLayout(self)
@@ -221,9 +246,12 @@ class Box(QWidget):
     def show_data(self, data):
         for w in self.widgets:
             self.layout().removeWidget(w)
-            for x in ('toggled',):
+            for x in ('toggled', 'hyperlink_activated'):
                 if hasattr(w, x):
-                    getattr(w, x).disconnect()
+                    try:
+                        getattr(w, x).disconnect()
+                    except TypeError:
+                        pass
             w.deleteLater()
         self.widgets = []
         for node in data['nodes']:
@@ -237,6 +265,7 @@ class Box(QWidget):
             self.widgets.append(h), self.layout().addWidget(h)
             for i, declaration in enumerate(node['css']):
                 d = Declaration(data['html_name'], declaration, is_first=i == 0, parent=self)
+                d.hyperlink_activated.connect(self.hyperlink_activated)
                 self.widgets.append(d), self.layout().addWidget(d)
 
         h = Heading(_('Computed final style'), parent=self)
@@ -263,6 +292,8 @@ class Box(QWidget):
 
 class LiveCSS(QWidget):
 
+    goto_declaration = pyqtSignal(object)
+
     def __init__(self, preview, parent=None):
         QWidget.__init__(self, parent)
         self.preview = preview
@@ -285,6 +316,7 @@ class LiveCSS(QWidget):
         s.addWidget(la)
 
         self.box = box = Box(self)
+        box.hyperlink_activated.connect(self.goto_declaration)
         self.scroll = sc = QScrollArea(self)
         sc.setWidget(box)
         sc.setWidgetResizable(True)
@@ -376,3 +408,6 @@ class LiveCSS(QWidget):
     def stop_update_timer(self):
         self.update_timer.stop()
 
+    def navigate_to_declaration(self, data, editor):
+        print (data)  # TODO: Implement this
+