Look! A #LibreOffice feature you may not know about ๐Ÿ˜‰ When exporting a #PDF the "Hybrid PDF" option embeds the original file. Then anyone with a PDF reader can view the file โ€“ and LibreOffice users can edit it too: https://wiki.documentfoundation.org/Faq/Writer/PDF_Hybrid#What_is_a_hybrid_PDF_file? #foss #OpenSource
Frequently asked questions - Writer - The Document Foundation Wiki

@libreoffice won't it increase the file size?

@sagir42 @libreoffice it will. Depending on the structure, content and features of a doc, the increased size is anywhere between "insignificant" and "magnitudes".

E.g. some complex object with large amounts of data that outputs a simple chart might use megabytes of storage in ODF and a few kilobytes in the PDF. So when the ODF is embedded it'll increase storage significant. Such cases are rare though.