Unexpected Application Error!

Cannot read property 'minifig_id' of undefined

TypeError: Cannot read property 'minifig_id' of undefined
    at _d (http://localhost:45678/static/js/main.1017b58b.js:2:487765)
    at ks (http://localhost:45678/static/js/main.1017b58b.js:2:69117)
    at _l (http://localhost:45678/static/js/main.1017b58b.js:2:126230)
    at yc (http://localhost:45678/static/js/main.1017b58b.js:2:115336)
    at vc (http://localhost:45678/static/js/main.1017b58b.js:2:115264)
    at xc (http://localhost:45678/static/js/main.1017b58b.js:2:115127)
    at sc (http://localhost:45678/static/js/main.1017b58b.js:2:111907)
    at ac (http://localhost:45678/static/js/main.1017b58b.js:2:110458)
    at j (http://localhost:45678/static/js/main.1017b58b.js:2:146257)
    at MessagePort.M (http://localhost:45678/static/js/main.1017b58b.js:2:146791)