The plugin works by inserting a frontscript that overrides an IDE function named seMatchingDefinitions. This function the the location of a handler when you right-click on one in the Script Editor.

When you right-click on a handler name in the LiveCode Script Editor, LiveCode looks through the stack containing the script's object to find a match. No frontscripts, backscripts or libraryStacks are searched which makes this feature much less useful.

For example, assume I am editing a script in one of my stacks and come across a function named BooleanToTrueFalse that resides in the script of a library stack.

If I right-click on the handler then Go to definition will be disabled. Since the handler isn't defined in any scripts of the stack the object is in LiveCode doesn't find any matches.

With the plugin installed Go to definition is enabled because the BooleanToTrueFalse handler definition is located in a stack listed under the libraryStacks.

Selecting Go to definition opens the BooleanToTrueFalse handler.

An extra feature included in the plugin has to do with behaviors. If you double-click on the Behavior label of an object then the behavior script will open in the script editor.