I love the CKS Dev extension. Since it does not work for VS2019 anymore, I decided to port the most important features.
Listens to all changes for files of type TemplateFile and copies them to SharePoint root. Event if the files are modified outside of VisualStudio (TypeScript Transpiler, Bundler, etc.)
Some ideas are from the CKSDev extension (https://archive.codeplex.com/?p=cksdev) but the code is completely new.