I've compiled a list of some things I think it will be useful to learn for front-end developers in 2021.
If it's been a while it might be time to revisit and make sure you're up to date with the latest standards.
Static site generators are also quite popular and work well for smaller projects.
PWA's have been around for a while but with more and more focus being put on website performance it's a good opportunity to learn something new & improve your projects.
If you have any additional suggestions leave them in the comments and share what you will be learning this year.