Your screenshot shows that it has something to do with footnotes. There's very little you can do about it. If you use the single-line composer, try the paragraph composer instead -- this has shown to fix some of these problems. Or move a footnote so that the page composes differently, or change the composition of one or more previous spreads so that the problem page composes differently. Not really satisfactory, but if all else fails you have little choice.
I am sad. I just ran into the same problem getting the header of the line in another text. And out of this problem I am getting error report while transferring the text. And I'm having constant crashing issues. Version 16.1 did not have these problems. Unfortunately, I deleted version 16.1 as it would solve the above problems. And now I can only proofread. I can't make a new book.