Issue while loading or creating articles

[Gunlek]

Issue Overview

Can't edit or create articles using Gunteberg editor because of an error that show up everytime I'm trying

Steps to Reproduce (for bugs)

1. Go to article list
2. Click "edit article" or "add article" using Gunteberg editor

Expected Behavior

The Gunteberg editor should appear allowing us to write or continue our work

Current Behavior

Wordpress is display a message to copy post, copy error or attempt recovery. The "copy error" result is the following:
TypeError: Cannot read property 'level_1' of undefined at http://website_url/wp-content/plugins/gutenberg/editor/build/index.js?ver=1517908162:11:13443 at n (http://website_url/wp-content/plugins/gutenberg/editor/build/index.js?ver=1517908162:6:21464) at c (http://website_url/wp-content/plugins/gutenberg/editor/build/index.js?ver=1517908162:6:17635) at c (http://website_url/wp-content/plugins/gutenberg/editor/build/index.js?ver=1517908162:11:13401) at beginWork (http://website_url/wp-content/plugins/gutenberg/vendor/react-dom.min.3583f8be.js:133:398) at d (http://website_url/wp-content/plugins/gutenberg/vendor/react-dom.min.3583f8be.js:158:393) at f (http://website_url/wp-content/plugins/gutenberg/vendor/react-dom.min.3583f8be.js:159:214) at g (http://website_url/wp-content/plugins/gutenberg/vendor/react-dom.min.3583f8be.js:159:462) at t (http://website_url/wp-content/plugins/gutenberg/vendor/react-dom.min.3583f8be.js:167:3) at x (http://website_url/wp-content/plugins/gutenberg/vendor/react-dom.min.3583f8be.js:166:247)

Possible Solution

Screenshots / Video

Related Issues and/or PRs

Todos

• Tests
• Documentation

[twsp]

I'm having trouble understanding how to recreate this bug. Could you include some screenshots to help explain exactly what you're doing?

[youknowriad]

These issues #5001 #4753 #4437 and #3747 are all related to the same error. Though we're not being able to reproduce properly yet.

I'm closing all these issues and consolidate in #4437