Replace Tonga with Bifroest.

 * FIXES #19728: https://bugs.torproject.org/19728
 * CLOSES #19690: https://bugs.torproject.org/19690

src/or/config.c

@@ -869,8 +869,8 @@ static const char *default_authorities[] = {
   "dizum orport=443 "
     "v3ident=E8A9C45EDE6D711294FADF8E7951F4DE6CA56B58 "
     "194.109.206.212:80 7EA6 EAD6 FD83 083C 538F 4403 8BBF A077 587D D755",
-  "Tonga orport=443 bridge "
-    "82.94.251.203:80 4A0C CD2D DC79 9508 3D73 F5D6 6710 0C8A 5831 F16D",
+  "Bifroest orport=443 bridge "
+    "37.218.247.217:80 1D8F 3A91 C37C 5D1C 4C19 B1AD 1D0C FBE8 BF72 D8E1",
   "gabelmoo orport=443 "
     "v3ident=ED03BB616EB2F60BEC80151114BB25CEF515B226 "
     "131.188.40.189:80 F204 4413 DAC2 E02E 3D6B CF47 35A1 9BCA 1DE9 7281",