Welcome AlfLibreCad210!
You can't compare LibreCAD plugins with AutoCAD Lisp!
The LibreCAD plugins interface is very rudimentary compared to AutoCAD's Lisp scripting engine.
With LibreCAD plugins you can just modify the current drawing, no access to the GUI or anything else.
You can take a look at my recent post as a starting point.
https://forum.librecad.org/I-need-detailed-documentation-on-developing-LibreCAD-plugins-tp5725201p5725206.htmlThere is no explicit documentation, have a look at the existing plugins to get an idea what's possible.
Armin
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