Move leaving book under "Details"

After analyzing a game, under the "Details" tab, there is a space provided for "Move Leaving Book," but there is no move provided. 

I am using Google Chrome on a Windows operating system.

This issue occurs for me after I select "Analysis" immediately after completing a game, selecting "Analyze" for an older game, and selecting "Game Review" on an analysis board. This has occurred for me with every opening. I am yet to find a scenario where this issue does not occur.  

Apologies if there is already a forum for this topic.

I don't think it has ever had a value. The Book Moves 5 does convey the essence, i.e Whites move 3. The book move color rendering also conveys the last book move, though it is black and not brown. ( as pointed out in recent post, recent post Suggestion or bug idk)

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