From 824b38332c4cd23bf343e8510214f0b56212721c Mon Sep 17 00:00:00 2001
From: Francis Lachapelle <flachapelle@inverse.ca>
Date: Fri, 17 Apr 2020 12:11:01 -0400
Subject: [PATCH] fix(preferences): avoid exception when parsing
 PreventInvitationsWhitelist

Fixes #5006
---
 UI/PreferencesUI/UIxJSONPreferences.m | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/UI/PreferencesUI/UIxJSONPreferences.m b/UI/PreferencesUI/UIxJSONPreferences.m
index 98bcb9fe9..ebfc34141 100644
--- a/UI/PreferencesUI/UIxJSONPreferences.m
+++ b/UI/PreferencesUI/UIxJSONPreferences.m
@@ -465,7 +465,7 @@ static SoProduct *preferencesProduct = nil;
   // sorry about this engineering brain fart!
   v = [[settings objectForKey: @"Calendar"] objectForKey: @"PreventInvitationsWhitelist"];
 
-  if (v && [v isKindOfClass: [NSString class]])
+  if (v && [v isKindOfClass: [NSString class]] && [v length] > 0)
     {
       [[settings objectForKey: @"Calendar"] setObject: [v objectFromJSONString]
                                                forKey: @"PreventInvitationsWhitelist"];