How to preview external files bookmarked in the project bookmarks

I want to read or see files project bookmarks on the below windows. What should I do…?
When I select normal files in project bookmarks, the below window shows some unreadable codes.
My current scrivener version: windows Beta (955095) 64-bit - 13 6 2020

This is a bug which has been fixed and will be available in the next update.