# @polkadot/extension-base Functions, classes and other utilities used in `@polkadot/extension`. These include: - background script handlers, - message passing, - scripts injected inside pages. They are primarily meant to be used in `@polkadot/extension`, and can be broken without any notice to cater for `@polkadot/extension`'s needs. They are exported here if you wish to use part of them in the development of your own extension. Don't forget to add `process.env.EXTENSION_PREFIX` to separate ports and stores from the current extension's ones.