TrustedXFF installed via `maintenance/install.php --with-extensions` and upon hitting load.php:
```
PHP Warning: fopen(cache/trusted-xff.cdb): failed to open stream: No such file or directory in vendor/wikimedia/cdb/src/Reader/PHP.php on line 72
PHP Fatal error: Uncaught Error: Call to a member function getCode() on null in includes/user/User.php:1774
```
```
[proxy]: proxying request - /load.php?debug=false&lang=en&modules=jquery%2Cmediawiki%7Cmediawiki.base&only=scripts&skin=vector&version=0srjkld to 127.0.0.1:9412
[Mon Jun 25 16:35:48 2018] PHP Warning: fopen(cache/trusted-xff.cdb): failed to open stream: No such file or directory in vendor/wikimedia/cdb/src/Reader/PHP.php on line 72
[Mon Jun 25 16:35:48 2018] PHP Fatal error: Uncaught Error: Call to a member function getCode() on null in includes/user/User.php:1774
Stack trace:
#0 includes/user/User.php(5460): User::getDefaultOptions()
#1 includes/user/User.php(3144): User->loadOptions()
#2 includes/context/RequestContext.php(336): User->getOption('language')
#3 includes/Message.php(380): RequestContext->getLanguage()
#4 includes/Message.php(1296): Message->getLanguage()
#5 includes/Message.php(848): Message->fetchMessage()
#6 includes/Message.php(940): Message->toString('text')
#7 includes/exception/MWExceptionRenderer.php(201): Message->text()
#8 includes/exception/MWExceptionRenderer.php(140): MWExceptionRenderer::msg('internalerror', 'Internal error')
#9 includes/exception/MWExceptionRenderer.php(54): MWExceptionRenderer::reportHTML(Object(Cdb\Exception))
#10 includes/exception/MWExceptionHandler.php in includes/user/User.php on line 1774