This Easy and Step-by-Step Tutorial shows you How to Manually Install Processing Libraries on Linux.
If you want to Expand the Processing Design Features then you need to Install some Contributed Library that has been Developed to Extend the Processing Design Capabilities.
For some Special Library that is Not in the Processing Repositories then you will need to Download and Manually Install this Guide for Linux.
The Instructions, Commands and Descriptions for Manually Install Processing Libraries Linux Guide give Focus only to the Essentials.
Double-Click on Library Archive and Extract Content into:
Processing 3 Tutorials on How to Getting-Started Using LibrariesProcessing Quick Tutorials