se.css has font-size: 0 hack for Kobo that should be in a separate kobo.css

[frank-murphy]

se.css defines these:

section[epub|type~="titlepage"] h1,
section[epub|type~="titlepage"] p,
section[epub|type~="colophon"] h2,
section[epub|type~="imprint"] h2{
        font-size: 0; /* Required for Kobo not to add an extra page to the title */
        left: -999em;
        position: absolute; /* Required for Kindle */
}

So these Kindle- and Kobo-specific tweaks are included in the "compatible" and "advanced" epubs that are specifically for non-Kindle or Kobo readers. I would expect them to only be added to the Kindle and Kobo files.

(I noticed because this font-size: 0 tweak is weirdly visible in KOReader and Librera.)