@JSWolf
This plugin is definitely ePub compatible.
&
Shy; is a stantard HTML entity supported since HTML 3.2 and clearly defined in HTML 4. It's present in the
W3G XHTML 1.1 dtd, and being ePub 2 based on XHTML 1.1 it definitely includes &
shy; (even if you don't like it).
However not every ePub reader implements the rendering of this special character. Some of them do it partially. Other shows it as expected. This is the same as other CSS features which may or may not be implemented in a specific reader.