From 6bbb5fa5a47d060bfac233020b3c9dd210a7cce6 Mon Sep 17 00:00:00 2001
From: ClemensF <fischer.clemens@gmail.com>
Date: Sat, 24 Oct 2020 10:23:00 +0200
Subject: [PATCH] Update TileSource.cs

---
 MapControl/Shared/TileSource.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/MapControl/Shared/TileSource.cs b/MapControl/Shared/TileSource.cs
index 18afc0d1..dc61c79c 100644
--- a/MapControl/Shared/TileSource.cs
+++ b/MapControl/Shared/TileSource.cs
@@ -32,9 +32,9 @@ namespace MapControl
             get { return uriFormat; }
             set
             {
-                uriFormat = value;
+                uriFormat = value?.Replace("{c}", "{s}"); // for backwards compatibility since 5.4.0
 
-                if (Subdomains == null && uriFormat.Contains("{s}"))
+                if (Subdomains == null && uriFormat != null && uriFormat.Contains("{s}"))
                 {
                     Subdomains = new string[] { "a", "b", "c" }; // default OpenStreetMap subdomains
                 }