noVNC doesn't warn about password length limit

[ThomasBaruzier]

Describe the bug
If my password is password, password123 will let me in
...

To Reproduce
Try to log in with the right password with extra characters

Expected behavior
Consider it a wrong password

Client (please complete the following information):

• OS: Latest Arch linux
• Browser: Any
• Browser version: Tested on latest firefox, safari, chromium, chrome

Server (please complete the following information):

• noVNC version: [e.g. 1.0.0 or git commit id]
• VNC server: TigerVNC
• WebSocket proxy: websockify + nginx

[pdlan]

This is because the default "VNC authentication" security type only uses the first eight characters of the password. You should use other security types if you need a longer password.

[CendioOssman]

Indeed. However, we could probably be better about warning users that aren't that familiar with VNC.

[CendioOssman]

Also see TigerVNC/tigervnc#370 for the same discussion in that project.