Extract content from backup files without restoring?

[pgorod]

Hi

sorry if this is not the right place to ask...

I see that the backups are in a tar format. Inside them I find the data I want to extract, from an add-on:

a0d7b954_bookstack.tar.gz

I want to get to the data, but not necessarily to restore it in HASS. I would like to just get the Bookstack content, I assume there's an SQL dump in there somewhere?

I extract the tar.gz and I am left with a binary file called a0d7b954_bookstack but I can't open it. Is there a way to open it in Windows or Linux and get to whatever is inside, in a usable format?

Thanks in advance for any advice!