I have read the other texts in ask.libreoffice.org. If they contain the answer, they are obscure.
I want to search for a section of text containing something, such as “. Text” in a large document. I want to replace with:
". " + New Paragraph + “Text”
How do I do this?
Find/Replace. In the Search for box, enter \. (.*). In the Replace box, enter .\n$1. Click Other options, tick Regular expressions. Replace all.
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You can use the Alternate Find and Replace add-on to do it.