These are English language-hosted sites in the United States, so posting in German here causes extra effort on non-German native speakers to translate the post, or to ignore it entirely. There is a German language Pages community page and even an Apple Communities Site map in German.
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Finding/Replacing Paragraph and Line Breaks in Pages
I often receive files that are still formatted with a paragraph break at the end of a line, like in the days of old typewriters. (Most people don't know the difference between line breaks and paragraph breaks anyway.)
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In Pages, a hard return and a paragraph break are identical — a linefeed character (e.g. \n or u+000a). A soft return (or formally a line separator) formed with a shift+enter is a different character (e.g. \i, u+2028).
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Unfortunately, the search/replace function in Pages – as in Word – fails in such cases!
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Never implemented in Pages after Oct 2013, the Word and LibreOffice Writer applications do have the ability to find and replace styles and even have regular expression (now called Wild cards) searches.
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For longer texts, I'm effectively forced to perform such replacements in an expensive layout program.
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There is the free LibreOffice Writer that may preclude expensive layout programs. It all depends on the content and your goals for that text.
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Reformatting received text in Pages (or Word) is therefore rather limited – or time-consuming.
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It can be arduous in Pages, depending upon the content and your goal, but not in the applications I mentioned above.
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Some PDF-to-document converters write out every line of text like it was scanned and end each of those strings with a paragraph (linefeed) mark. That is a mess in any word-processing application. Although Pages can find and remove those individual paragraph marks, then you arrive at a blob of text that requires additional formatting.
