It would be great if there was a parameter $wgExtractsIncludeClasses where classes could be defined that should be included in the text extracts. Often, I use some kind of div with styling informtion also for the first paragraph that will not be included in the extracts. If I want this to work, I always have to start with some plain text, which is quite unflexible.
Topic on Extension talk:TextExtracts
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