diff --git a/digitalstrategie/settings/dev.py b/digitalstrategie/settings/dev.py
index d10c4a65..15ac71a6 100644
--- a/digitalstrategie/settings/dev.py
+++ b/digitalstrategie/settings/dev.py
@@ -68,6 +68,7 @@
 ]
 CSP_IMG_SRC = [
     "'self'",
+    "data:",
     "https://captcha-numbers-stage.liqd.net",
     "https://stats.liqd.net",
     "https://berlin.de",