So I do some front end work, I work across the stack. At the minute the front end related work relates to
optimising the code that runs the tooling used to build production web sites and applications: benchmarking, looking for where things can be sped up, looking for simpler ways of doing things, removing redundant stuff.
integrating opentelemetry reporting (essentially logging in a specific format) the frontend and passing trace IDs into the backend, allowing us to trace back and forth through the system as a whole, frontend thru back
At my previous job, the things that took by far and away the most work were
writing logic to be used for user authentication in all apps (four months of writing a small amount of pure JS code + a lot of tests, then maybe a day or two of writing the React code that handled the UI)
writing a reusable white label component library. I was a designer prior to becoming a developer, and knowledge of design rules helped with respect to typography-related conditions, but most of the work was to do with producing the API for it. Note I’ve done this at every job I’ve worked at, and this, like all the others, I would class as failure in most respects; not worth the effort.
writing collection of TS libraries for use across all FE apps (formatting, state management, i18n handling, etc). Tooling was the thing that took most work: writing scripts, publishing, ensuring dependencies kept up to date, etc.
I could keep going, but hopefully should give some insight.