Book & Quill turns page automatically after A space on 2nd page

Hi Mojang. I was playing Minecraft 19w12b and was using A Book & Quill. I was somehow trying to type on the 2nd page, however, when I pressed the spacebar, it went to the next page. It's highlighting the next arrow and IDK how to "not" do that. Please fix this bug ASAP.

From, NathanPatty