@LittleBiG I’ve just created a function to deal with multiple entries for a Duden dictionary optimized for Koreader in my script
Pocketbookdic.
Currently, it just prefixes with a superscript Roman numeral the definitions of entries with an identical keyword.
I’ve no idea why line breaks are disregarded. However, I’ve stumbled over both </br> and <br/> and it seems feasible that at least one is not recognized as a correct line break tag.
If you an provide a link to a dictionary with a relevant entry, I am willing to test and add a conversion to the tags for Koreader optimized part of the script.