mdpdf: ReferenceError: path is not defined

Trying to run on Ubuntu 16:

ReferenceError: path is not defined
    at processSrc (/usr/local/lib/node_modules/mdpdf/src/utils.js:51:23)
    at Object.$.each (/usr/local/lib/node_modules/mdpdf/src/utils.js:59:23)
    at initialize.exports.each (/usr/local/lib/node_modules/mdpdf/node_modules/cheerio/lib/api/traversing.js:300:24)
    at Object.qualifyImgSources (/usr/local/lib/node_modules/mdpdf/src/utils.js:58:12)
    at prepareHeader.then.then.then.then.mdDoc (/usr/local/lib/node_modules/mdpdf/src/index.js:116:23)
    at tryCatcher (/usr/local/lib/node_modules/mdpdf/node_modules/bluebird/js/release/util.js:16:23)
    at Promise._settlePromiseFromHandler (/usr/local/lib/node_modules/mdpdf/node_modules/bluebird/js/release/promise.js:512:31)
    at Promise._settlePromise (/usr/local/lib/node_modules/mdpdf/node_modules/bluebird/js/release/promise.js:569:18)
    at Promise._settlePromise0 (/usr/local/lib/node_modules/mdpdf/node_modules/bluebird/js/release/promise.js:614:10)
    at Promise._settlePromises (/usr/local/lib/node_modules/mdpdf/node_modules/bluebird/js/release/promise.js:694:18)
    at Promise._fulfill (/usr/local/lib/node_modules/mdpdf/node_modules/bluebird/js/release/promise.js:638:18)
    at /usr/local/lib/node_modules/mdpdf/node_modules/bluebird/js/release/nodeback.js:42:21
    at FSReqCallback.readFileAfterClose [as oncomplete] (internal/fs/read_file_context.js:54:3)

with node v11.8.0, npm 6.5.0