The easiest approach is be to use an extension like Tampermonkey, which can load (and reload) “scripts” from a web server. There are a few project templates on GitHub with Typescript+WebPack (e.g. https://github.com/xiaomingTang/template-ts-tampermonkey). You can automate with any of your favorite Typescript libs, from the comfort of your IDE, with hot reload included.. Pretty nifty, and projects can quickly get pretty big that way! I usually have one “script” that has broad permissions (e.g. all sites) with some form of router at the root of the code that branches to the different sites to evaluate.