A dev container can now be rebuilt without using Docker's image layer cache. When connected to a dev container, there is the additional Rebuild Without Cache command. When a local folder with a dev container configuration is open, there is the additional Rebuild Without Cache and Reopen in Container command.
There is now a devcontainer Command Line Interface (CLI) that can be installed. This allows you to open a folder within a dev container, and to build the dev container image from your terminal.