diff --git a/bebop/__main__.py b/bebop/__main__.py
index ec4e18e..90e5d71 100644
--- a/bebop/__main__.py
+++ b/bebop/__main__.py
@@ -20,7 +20,7 @@ def main():
         user_data_path.mkdir()
 
     cert_stash_path = user_data_path / "known_hosts.txt"
-    cert_stash = load_cert_stash(cert_stash_path)
+    cert_stash = load_cert_stash(cert_stash_path) or {}
     try:
         Browser(cert_stash).run(start_url=start_url)
     finally:
diff --git a/bebop/bookmarks.py b/bebop/bookmarks.py
index 00be956..02cb59d 100644
--- a/bebop/bookmarks.py
+++ b/bebop/bookmarks.py
@@ -1,4 +1,3 @@
-import io
 from pathlib import Path
 
 from bebop.fs import get_user_data_path