diff --git a/qutebrowser/config/configdata.py b/qutebrowser/config/configdata.py
index fbe5c2319..d8808bdc1 100644
--- a/qutebrowser/config/configdata.py
+++ b/qutebrowser/config/configdata.py
@@ -841,7 +841,7 @@ def data(readonly=False):
              "required to exactly match the requested domain.\n\n"
              "Local domains are always exempt from hostblocking."),
 
-            ('enable-pdfjs', SettingValue(typ.Bool(), 'true'),
+            ('enable-pdfjs', SettingValue(typ.Bool(), 'false'),
              "Enable pdf.js to view PDF files in the browser.\n\n"
              "Note that the files can still be downloaded by clicking"
              " the download button in the pdf.js viewer."),