Not sure if this is a Calibre or Sigil related question, so I hope someone can guide me in the right direction?
At present I insert a para break by using <p class="calibre7"> </p> to reflect a corresponding space in the hard copy of the book. Using Enter/Space in Sigil to create.
Code View:
<p class="calibre7">But it was clear that the lady did not believe him.</p>
<p class="calibre7"> </p>
<p class="calibre">It was about ten o’clock that night.</p>
Book View:
But it was clear that the lady did not believe him.
It was about ten o’clock that night.
This works fine when I transfer the epub onto my tablet using Aldiko as the reader.
However I find that now if I have to convert the book again (for covers etc.) that Calibre (Version 9.28) removes the   leaving just <p class="calibre7"></p>, effectively removing the space originally created. I'm sure this didn't happen in previous versions of Calibre.
If in Sigil (Version 0.7.2) I just press enter to create a space it shows up as <p class="calibre7"><br /></p> which creates the space in Sigil, but this doesn't show up on the E-Reader.
What should I now be using to insert a space that Calibre will not remove in subsequent conversions, and that the E-reader can recognize?
Thanks in advance.