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LibreOffice also ships with a modified theme which looks native on GTK-based Linux distributions. It also renders fonts via Cairo on Linux distributions; this means that text in LibreOffice is rendered the same as the rest of the Linux desktop.[81]
LibreOffice supports the editing of PDF documents by default and opens them in the LibreOffice Draw application. You can open Draw directly and use the File menu to load PDF documents, or use the startup wizard instead
If you really want an exact result, copy paragraph by paragraph for your PDF viewer into a text file and check it with the wc -w tool. The reason why not to use pdftotext in that case is: mathematical formulas may get also into the output and regarded as "words"