rugk/xenforo-threema-gateway

## Steps to reproduce

1. 
2. 

### What happens:


### What should happen:


## Status

OS: Linux
PHP version: 
XenForo version: 
add-on version: 
cURL version: 

<!-- Copy the status message from the ACP in the settings, you do not have to include your remaining credits) -->  

```
Sodium version: x.y.z
Version of Threema PHP SDK: x.y.z
…
...
```

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