Can't create child field

Web Scraper version: 0.4.2
Chrome version: 77.0.3865.75 64bit (Clean Chrome, without any other active extensions)
OS: MacOS 10.13.6 (17G8030) and Win7


{"_id":"test","startUrl":[""],"selectors":[{"id":"name","type":"SelectorText","parentSelectors":["_root"],"selector":"a.title","multiple":true,"regex":"","delay":0},{"id":"element created in \"name\"","type":"SelectorText","parentSelectors":["_root"],"selector":"p.description","multiple":false,"regex":"","delay":0}]}

Error Message:

No errors.
If I create a new sitemap, I can create only selectors as a child of "_root" and any other selector I made doesn't appear in the "Parent Selectors" field.
If I edit an old sitemap that has already hierarchical structure with selectors and child of them, in the "Parent Selectors" field I can select old selectors as "parents" but it doesn't show the selectors I created in this session.

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  4. A new popup window should appear.
  5. Go to “Console” tab. You should see Web Scraper log messages and errors there.