github.com/hashicorp/packer@v1.14.3/website/content/partials/plugins/plugin-location.mdx (about)

     1  Upon initialization of Packer, all the installed plugins will be automatically discovered.
     2  
     3  Packer plugins must be located under the `plugins` sub-directory under Packer's main config directory
     4  [PACKER_CONFIG_DIR](/packer/docs/configure#packer-s-config-directory).
     5  If `PACKER_CONFIG_DIR` is either unset or empty, a default value of `$HOME/.config/packer/plugins` on UNIX,
     6  or `%APPDATA%\packer.d\plugins` for Windows, will be used.
     7  
     8  If the `PACKER_PLUGIN_PATH` environment variable is set, it will be used instead of `PACKER_CONFIG_DIR/plugins`.
     9  
    10  -> **Note:** Prior to Packer 1.11 the `PACKER_PLUGIN_PATH` environment variable supported values containing
    11     multiple directories. Starting with Packer 1.11 and later this variable only supports a single directory.