It does indeed look promising! Unfortunately, entering
@@
on a new line is not doing anything for me over here; the list of other notes within the open notebook does not appear as shown in @roman_r_m's example.
other plugins work as intended (ie; TOC, Line Numbers)
I restarted Joplin after activating the plugin (pulled the 0.0.2 .jpl)
I'm not sure the version required is all that clear with this plugin. I did the same as you. I downloaded the plugin via Joplin v1.6.8 and found it did not work. I could not see a minimum Joplin version on GitHub so I had to look in the jpl and saw "app_min_version": "1.7",.
Roman I just installed 1.7.6 for Windows desktop, restarted, and I also see nothing happening when I type @@ on an otherwise empty line in the markdown editor.
Try fully shutting down Joplin (File > Quit) and starting it again (Default computer fault-fixing ). Worked for me, which is odd because Joplin restarts itself when a plugin is installed.