Error on page load: `compact(): Undefined variable: operator`

[xBytez]

Describe the bug
Any page post-login returns an unknown error.

Steps To Reproduce
Steps to reproduce the behavior:

1. Login
2. Try any link

Expected behavior
It'll work as intended. Can't be any more clear and concise than that.

Screenshots
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Your Configuration (please complete the following information):

• Exact BookStack Version (Found in settings): v0.24.1
• PHP Version: PHP 7.3.0RC4
• Hosting Method (Nginx/Apache/Docker): nginx/1.15.5

Additional context
Add any other context about the problem here.

Might be related: laravel/framework#25192