Converting multi column PDFs

1. Install: k2pdfopt (make sure to enter the captcha on the left side of the page)
2. Copy the file to your bin directory: sudo mv k2pdfopt /usr/local/bin
3. Make it executable: sudo chmod a+x /usr/local/bin/k2pdfopt
4. Add a .desktop application for k2pdfopt: nano ~/.local/share/applications/k2pdfopt.desktop

[Desktop Entry]
Name=k2pdfopt
Exec=/usr/local/bin/k2pdfopt %f
MimeType=application/pdf;
Terminal=true
Type=Application
Categories=Application

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