I'm still looking for a robust replacement to create spacing.
Had not thought of your workaround.
The en, em, and thin space entities are all safe in Sigil and Calibre,
but some eReaders, especially Sony ones, cannot display them and you get "?" (question mark) or "¤" (undefined currency).
For scene breaks I use either of these dots or three tildes. They are all safe wherever I have tried them. The dot is barely noticable, if you are looking for sublety.
<div class="smallbullet">• • • • •</div>
div.smallbullet {
display: block;
text-align: center;
font-size: 0.7em;
margin-bottom: 0.8em;
margin-top: 0.8em;
margin-left: 0;
margin-right: 0;
border: 0;
text-indent: 0;
}
<div class="dot">⋅ ⋅ ⋅ ⋅ ⋅</div>
div.dot {
display: block;
text-align: center;
margin-bottom: 0.8em;
margin-top: 0.8em;
margin-left: 0;
margin-right: 0;
border: 0;
text-indent: 0;
}