On the features in the 3click2edit plugin,
I have reinvented this a number of times, especially in package I call “Smart Show code” which displays the content of “code tiddlers” and allows click to edit. However being able to defeat this is also helpful if you want to select and copy code without editing.
My solution has no Javascript and can be distributed as a macro.
My point is if there is too many issues with supporting 3click2edit we could build an equivalent quite easily.
Not withstanding this, this thread stands on its own for the more general discussion "How to get plugins from github?"