Can't select a Content relationship field after updating a custom-type

I am having issues where I've added a Content Relationship Field to an existing Slice and when going to the document to add it in, it doesn't open the sidebar for me to select content.
There is this error message in the console. Any Ideas?

main.js:373 Uncaught TypeError: Cannot read property '1' of null
    at main.js:373
    at main.js:291
    at Function.m.some.m.any (underscore-1.8.2.min.js:5)
    at m.<computed> [as some] (underscore-1.8.2.min.js:5)
    at Object.N [as navigate] (main.js:291)
    at g (main.js:329)
    at Object.select (main.js:329)
    at HTMLDivElement.<anonymous> (main.js:464)
    at HTMLDivElement.dispatch (jquery-2.1.0.min.js:3)
    at HTMLDivElement.$event.dispatch (drag-tools-2.2x.js:378)
    at HTMLDivElement.r.handle (jquery-2.1.0.min.js:3)
    at HTMLDivElement.a (main.js:329)

I removed the Field placeholder value and it seems to have solved the problem.
The issue is either having a text value in the field placeholder or the placeholder starting with the Astrid * character.

This thread is being monitored as an open ticket in the issue tracker. We will update this post as we get more information. If you have a similar use-case, you can ‘Flag’ this topic to reopen.

Issue: https://github.com/prismicio/issue-tracker-wroom/issues/726

Hi Tyron,

Welcome to the community!

This is an interesting one that I haven't seen before. I was able to recreate this on my side and I've passed the example to the dev team to investigate.

Thanks.