Sync user settings

### Prerequisites

- [X] I checked to make sure that this issue has not already been filed;
- [X] This is not an ad/bug report.

### Problem description

There are a couple of existing feature requests for synchronising for filters (#158, #152) which don't cover the synchronisation of user settings. It would be good to cover everything, not just the filters.

### Proposed solution

Synchronise user settings.

### Additional information

_No response_