Without the newline iCal complains in the logs:

11-06-01 16:11:06 iCal[12955] Unexpected EOF, returning last token as fallback
2011-06-01 16:21:03 +02:00 · 2011-06-01 16:21:03 +02:00 · 710b518b0f
commit 710b518b0f
parent 5b9180c295
1 changed files with 1 additions and 1 deletions
--- a/radicale/ical.py
+++ b/radicale/ical.py
@ -52,7 +52,7 @@ def serialize(headers=(), items=()):
    for part in (headers, items):
        if part:
            lines.append("\n".join(item.text for item in part))
-    lines.append("END:VCALENDAR")
+    lines.append("END:VCALENDAR\n")
    return "\n".join(lines)