Importing built guide.html throws Unhandled promise rejection about snowman

[klembot]

Sorry, at the moment master is a bit of a work-in-progress. I would recommend using the commit 642c986 as jumping-off point.

[phivk]

thanks for the suggestion, I have checkout out 642c986, but I still get this Unhandled promise rejection error when I try to import /dist/guide.html into the Twine editor at https://twinery.org/2/#!/stories:

Unhandled promise rejection 
TypeError: t.attributes.position is undefined
Stack trace:
n/<.passages<@https://twinery.org/2/twine.js:1:211031
n@https://twinery.org/2/twine.js:1:210965
t.exports/<@https://twinery.org/2/twine.js:1:211710
t.exports@https://twinery.org/2/twine.js:1:211643
import/<@https://twinery.org/2/twine.js:1:209404
g@https://cdnjs.cloudflare.com/ajax/libs/core-js/2.4.1/core.min.js:8:10109
F/<@https://cdnjs.cloudflare.com/ajax/libs/core-js/2.4.1/core.min.js:8:10231
k@https://cdnjs.cloudflare.com/ajax/libs/core-js/2.4.1/core.min.js:8:14386

I tried checking out this slightly earlier commit dafdb2c and have generated /dist/guide.html via both npm run build and yarn build, but importing it produces the same error.