use key from url ?SID=...

.gitignore

@@ -32,3 +32,5 @@ package-lock.json
 /website/files/
 /website/images/
 /website/ads.txt
+
+.vercel

js/storage.js

@@ -512,6 +512,12 @@ Storage.initTestClient = function () {
 		sid = POKEMON_SHOWDOWN_TESTCLIENT_KEY.replace(/\%2C/g, ',');
 	}
 
+	if (!!Config.key) {
+		console.log('Using test client key', Config.key);
+		sid = (Config.key).replace(/\%2C/g, ',');
+		console.log('Using test client id', sid);
+	}
+
 	Storage.whenAppLoaded(function (app) {
 		var get = $.get;
 		$.get = function (uri, data, callback, type) {

testclient.html

@@ -27,8 +27,10 @@
 						Config.server = {
 							id: m[1],
 							host: m[2],
-							port: (m[3] && parseInt(m[3].substr(1))) || 8000
+							port: (m[3] && parseInt(m[3].substr(1))) || 8000,
 						};
+					} else if (m = /\?SID=(.+)/.exec(location.search)) {
+						Config.key = m[1];
 					} else {
 						alert('Unrecognised query string syntax: ' + location.search);
 					}