Half bug, half feature request:
Excerpts don’t play all that well with cards. When a post starts with a card and no custom excerpt is set, the resulting automatic excerpt can be pretty nonsensical. For example, if a post starts with a file card, the excerpt is the filename. Not very user friendly.
If the first item in the post is code with a script in it, it can also result in loading an unexpected script on the homepage of themes that display an excerpt, or console errors for badly formed javascript, when the script gets truncated at the end of the excerpt. Here’s an example illustrating the problem - the yellow area is the automatically generated Ghost excerpt.
That’s a code block, getting executed on the front page!