On: I created an open-source Hardware Hacking Wiki – w...

[hw-f3nter]

You are right! I encountered the same problem. Unfortunately, I didn't find a setting in Gitbook to change the preview text, just the preview image. It seems like it just takes the name of the first page 'Welcome to HardBreak' and adds the site name 'HardBreak' at the end. So I'd have to change the name of the first page, but a name like 'HardBreak - a Hardware Hacking Wiki' or something similar would look weird on the website, I think. I haven't found a good solution for that yet.

[sen → hw-f3nter]

I think having it in the homepage title is fine. I do it for most sites I build for exactly this reason.

“HardBreak - Open-Source Hardware Hacking Wiki”

Looks fine as a title, and helps for embeds/sharing.