Improve frontend unit tests

In our architecture, the frontend is **not** responsible for a lot of logic (the filters in the details page are all done in the backend for example); however there's still a lot of functions that we use in the frontend that are not being covered and this should be addressed.

The issue names no files, existing test targets, or test command. Start by locating the frontend unit-test setup and inventorying uncovered frontend functions; done means adding useful unit coverage for the selected functions and confirming the frontend test suite passes.

Written by the indexing model from the issue text.