[GeoffR]

Originally Posted by npr

I see from your kepub hyphenation patch, you have a way to modify the kepub style sheet.
I also see from another post that chopped off bits of characters can be made to display correctly if a small amount of padding is added.
Adding the two bits of information and knowing nothing about the whole thing, I wondered if it's possible to create a patch to add a small amount of padding to the top of the kepub style sheet and if this would prevent the tops of tall characters being chopped off and displayed at the bottom of the previous page.

It is quite easy to replace a line in the built-in stylesheets with something else, as long as the replacement is not longer than the original line. The question would be: what line in the original stylesheet could I replace?

I think this is all the built-in kepub stylesheet, but parts of it are included conditional on various device settings, and there could be other bits I don't know about.

Spoiler:

body, p { line-height: %1 !important; }
body { margin: 0px %1% 0px %2% ! important;}
body {margin-top:0px; margin-bottom:0px;}
body { margin: 0px; }
img { display: block; margin-left: auto !important; margin-right: auto !important; width: auto !important; height: auto !important; }
body { -kobo-font-sharpness: %1; -kobo-font-thickness: %2; }
html { word-wrap: break-word; }
body { -kobo-font-hintstyle: 1;}
a:link, a:visited, a:hover, a:active { border-bottom: 1px dotted black !important; color: #696969 !important; }
* { font-family: %1 !important; }
.KBHighlighting { background-color: #C6C6C6 !important; }       .KBStackKeyword, .KBSearchResult, .KBAnnotation, .KBHighlighting , KBAuthorAnnotation{ font-size: 100% !important; -webkit-text-combine: inherit !important; }  .KBSearchResult { background-color: #C6C6C6 !important; }       .KBStackKeyword a { color: black !important; }  .KBAuthorAnnotation, .KBAuthorAnnotationContinued { background-color: transparent !important; text-decoration: none !important; }       .KBStackKeyword[writingMode="horizontal-tb"] a { border-bottom: 1px solid black !important; }   .KBAuthorAnnotation[writingMode="horizontal-tb"], .KBAuthorAnnotationContinued[writingMode="horizontal-tb"] { border-bottom: 2px dotted black !important; }     .KBAnnotation[writingMode="horizontal-tb"], .KBAnnotationContinued[writingMode="horizontal-tb"] { border-bottom: 2px solid black !important; }  .KBStackKeyword[writingMode="vertical-rl"] a { border-right: 1px solid black !important; }      .KBAuthorAnnotation[writingMode="vertical-rl"], .KBAuthorAnnotationContinued[writingMode="vertical-rl"] { border-right: 2px dotted black !important; }  .KBAnnotation[writingMode="vertical-rl"], .KBAnnotationContinued[writingMode="vertical-rl"] { border-right: 2px solid black !important; }       .KBStackKeyword[writingMode="vertical-lr"] a { border-left: 1px solid black !important; }       .KBAuthorAnnotation[writingMode="vertical-lr"], .KBAuthorAnnotationContinued[writingMode="vertical-lr"] { border-left: 2px dotted black !important; }   .KBAnnotation[writingMode="vertical-lr"], .KBAnnotationContinued[writingMode="vertical-lr"] { border-left: 2px solid black !important; }
::selection { background: #FFFFFF !important; }
* { -webkit-hyphens: auto; }
* { -webkit-locale: '%1'; }
rt { font-family: 'A-OTF Gothic MB101 Pr6N' !important; }
body { width:100% !important; height: 100% !important; }
div, p { text-align: %1 !important; }

One of those lines is very long and has a lot of spaces, so it might be possible to remove some of the spaces and make room for some extra stuff.