Have you tried using a tab refresher? Sometimes it can help sustain the connection better.
If the login page isn't the issue, maybe try this:
1. Open login page
2. Open FeralHeart, attempt login, and close it (keep the login page open the entire time)
3. Refresh login page
4. Open FeralHeart again and spam the Login button (may take 2 or 3 or sometimes even more tries to connect)
If that still doesn't work, try opening your task manager (if you're on PC) and look for any other background programs that could be disrupting you and close them (via end task).
Hope this helps ya, fluff!