Also disable all externally-used functions for XML.

1 files changed, 10 insertions, 6 deletions

diff --git a/content_scripts/ui_component.coffee b/content_scripts/ui_component.coffee
index 5bb13496..e4cfc293 100644
--- a/content_scripts/ui_component.coffee
+++ b/content_scripts/ui_component.coffee
@@ -8,12 +8,16 @@ class UIComponent
   constructor: (iframeUrl, className, @handleMessage) ->
     styleSheet = document.createElement "style"
 
-    # If this is an XML document, nothing we do here works:
-    # * <style> elements show their contents inline,
-    # * <iframe> elements don't load any content,
-    # * document.createElement generates elements that have style == null and ignore CSS.
-    # We bail here if this is the case so we're polluting the DOM to no or negative effect.
-    return unless styleSheet.style
+    unless styleSheet.style
+      # If this is an XML document, nothing we do here works:
+      # * <style> elements show their contents inline,
+      # * <iframe> elements don't load any content,
+      # * document.createElement generates elements that have style == null and ignore CSS.
+      # If this is the case we don't want to pollute the DOM to no or negative effect.  So we bail
+      # immediately, and disable all externally-called methods.
+      @postMessage = @activate = @show = @hide = ->
+        console.log "This vimium feature is disabled because it is incompatible with this page."
+      return
 
     styleSheet.type = "text/css"
     # Default to everything hidden while the stylesheet loads.