How to add library to Sloeber

Question

Slober has a menu option: Arduino -> Add a library to the selected project

HOWEVER, the "Import Arduino libraries" dialog that comes up only shows 18 libraries, and has no obvious way to add more.

I selected Arduino -> How To, and selected "Add a library to a sketch", but it told me nothing new. It assumes the library I want to add is in the list, and says nothing about how that list itself is managed, where the libraries in it came from, how to add others, etc.

I theorized that Sloeber's list might be somehow generated from the one maintained by the Arduino IDE... but no, the list of libraries shown in Sketch -> Include library is ENORMOUSLY longer than Sloeber's list.

So... where, exactly, does Sloeber's library list come from, and how does one go about adding a library to it that's NOT in the list? Say...

• From whatever repository the Arduino IDE itself gets libraries from when you go to Library Manager (confession: I don't use Arduino often enough to know where those libraries are actually hosted, or who decides what qualifies to be listed. I assume it's something like MavenCentral and hosted by the Arduino organization... but I might be completely wrong)

• From a "zipfile" (containing whatever files, with whatever additional metadata, is required for Arduino's IDE to regard it as a valid library zipfile)

• From a random Github repo, like https://github.com/mrkaleArduinoLib/gbj_htu21 (with library.json, library.properties, and subdirectories for src/ and examples/)

• Juraj: In Arduino or in Window menu in Preferences in Arduino section in Library Manager subsection
• Juraj: the library folders are set in Preferences too
• Bitbang3r: (blush) Argh, I completely forgot that Slober has its own preferences that are separate from File -> Properties. (I do Arduino development just often enough to forget little details like that in between projects). Go ahead and list it as an answer, and I'll accept it :-)

Answer 1

In Arduino or in Window menu in Preferences

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