I was just playing with the custom recipe for wikipedia from this post:
https://www.mobileread.com/forums/showthread.php?t=41457
I wanted to look into trying to include images, so I yanked the beautiful soup function to see how the default HTML looked with images as an epub.
The first thing I noticed was that some of the text sizing changed pretty drastically - nearly everything was the same size. Digging into it, it looks like Calibre normalizes the div classes until nearly everything is using the same class, calibre4. I didn't test this in .5, but since the css handling has seen some pretty major changes I assume that it's quite different there.
An example (from the 'Tree' example article in the plugin):
Original HTML:
Code:
<div class="thumbcaption">
<div class="magnify"><a title="Enlarge" class="internal" href="/wiki/File:Leavessnipedale.jpg"><img width="15" height="11" alt="" src="/skins-1.5/common/images/magnify-clip.png"/></a></div>
<a title="Beech" href="/wiki/Beech">Beech</a> leaves.</div>
Calibre Generatet HTML:
Code:
<div class="calibre4">
<div class="calibre4"><a href="/wiki/File:Leavessnipedale.jpg" title="Enlarge"><img src="images/img2.png.jpg" width="15" height="11" alt="" class="thumbimage"/></a></div>
<a href="/wiki/Beech" title="Beech">Beech</a> leaves.</div>
</div>
calibre4 had been used previously as the class id for general content, as you can see above several new classes were introduced, but instead of incrementing to calibre5 and calibre6, calibre4 was re-used.
I've attached the plugin with the beautiful soup function removed, as this particular example is in the image caption.