Some runtimes other than Node.js have dropped support for external buffers.
On runtimes other than Node.js, node-api methods may return
napi_no_external_buffers_allowed to indicate that external
buffers are not supported. One such runtime is Electron as
described in this issue
electron/issues/35801.
In order to maintain broadest compatibility with all runtimes,
you may define NODE_API_NO_EXTERNAL_BUFFERS_ALLOWED in your addon before
includes for the node-api and node-addon-api headers. Doing so will hide the
functions that create external buffers. This will ensure a compilation error
occurs if you accidentally use one of these methods.
In node-addon-api, the Napi::Buffer::NewOrCopy provides a convenient way to
create an external buffer, or allocate a new buffer and copy the data when the
external buffer is not supported.