[bugfix] Update public/auth.js (#38)

trim trailing spaces from user input for Instance URL

Fix for Issue #37

Reviewed-on: https://codeberg.org/superseriousbusiness/masto-fe-standalone/pulls/38
Co-authored-by: daj <daj@findmyinbox.co.uk>
Co-committed-by: daj <daj@findmyinbox.co.uk>

public/auth.js

@@ -20,7 +20,7 @@ async function ready() {
 async function auth() {
   setMessage('Please wait');
 
-  const instance = document.getElementById('instance').value;
+  const instance = document.getElementById('instance').value.trim();
   const matches = instance.match(/((?:http|https):\/\/)?(.*)/);
 
   const protocol = matches[1];