Originally Posted by Bookpossum
Thanks for your comments, meeera and murg. Meeera, I wonder if your books were loaded before 2.1.5. That is, maybe murg and I are getting the problem with a book downloaded before the update, which has somehow retained the "memory" of the old thing with not splitting paragraphs.
I doubt that. I am sure the books are rendered each time it is opened.
I downloaded The Mapp and Lucia Omnibus and tried it. With the font settings I usually use, there was a lot of space at the bottom. And there were a few pages with a lot more space. But this is cause by the widows and orphans style setting. From what I can see, Kobo use 3 for both of these. The widows setting means that if a paragraph goes over the end of a page, it will put at least three lines together on the next page. The orphans setting means that a similar thing happens if the beginning of a paragraph is near the end of the page In this case, the if it can't keep three lines on the page, the paragraph will be pushed to the next page.
I edited the epub and changed the settings to zero for both. This causes the screen to be filled as much as possible.
But, there still seemed to be a lot of space at the bottom of each page. Some of this is because the epub has the top and bottom page margins set to 5pt. That plus the exact font size used, accounts for the rest of the space at the bottom.
If you want to see exactly how much space is wasted at the bottom, set the font to the smallest size and find a paragraph that is long enough to have a least three lines on each page. When you open the bottom menu, the gap you see between the last line of text and the line across the screen is the page bottom margin (5pts for this book). Plus, unless the screen is an exact multiple of the height of the text at that font size, whatever is leftover so that a partial line isn't displayed.