diff --git a/src/index.html b/src/index.html
index 446ff39..91cf952 100644
--- a/src/index.html
+++ b/src/index.html
@@ -202,6 +202,6 @@
 		</div>
 		<script src="/js/vendor/jquery.min.js"></script>
 		<script src="/js/vendor/bootstrap.min.js"></script>
-		<script src="/js/connectivity.js?v=5"></script>
+		<script src="/js/connectivity.js?v=6"></script>
 	</body>
 </html>
\ No newline at end of file
diff --git a/src/js/connectivity.js b/src/js/connectivity.js
index 73425ed..ec3cce7 100644
--- a/src/js/connectivity.js
+++ b/src/js/connectivity.js
@@ -9,6 +9,14 @@ function test_ipv4() {
 		dataType: "json",
 		timeout: 15000,
 		success: function(resp) {
+			if (resp.address.includes(":")) {
+				$p.find(".proto_supported").html("<span class='label label-warning' style='font-size:1em'>Browser error</span>");
+				$p.find(".proto_address").html("<span class='address'>n/a</span>");
+				$p.find(".proto_hostname").html("<span class='label label-warning'>Not tested</span>")
+				$p.find(".proto_isp").prev().html("Error")
+				$p.find(".proto_isp").html("Your browser doesn't support IPv6 properly. Please check out <a href='https://bugzilla.mozilla.org/show_bug.cgi?id=1709564'>this bug</a> if you are using Firefox.");
+				return;
+			}
 			$p.find(".proto_supported").html("<span class='label label-success' style='font-size:1em'>Supported</span>");
 			$p.find(".proto_address").html("<span class='address'>" + resp.address + "</span>");
 			$p.find(".proto_isp").html("<img class='img-flag' src='/img/flags/" + resp.country + ".png' title='" + resp.country + "' />" + resp.asn);