regarding the comment #1 question:

in the help for edit, when someone tries to edit a function that has been defined at the command line, the expected behavior is:

If NAME is the name of a command-line function, then an m-file
will be created to contain that function along with its
current definition.

sure enough, creating a function at the command line:

>> function y = myfun(x), y = 2(x); endfunction

>> myfun(4)
ans = 8

>> edit myfun.m

brings up the 'file does not exist, do you want to create it' dialog. if you say yes, it creates a myfun.m file in the current working directory, and the editor opens it showing the current Octave copyright header, template docsctring, and:

myfun is the command-line function:

function a = myfun (b)
  a = 2 * b;
endfunction

however, if you make another function that calls myfun, open it in the editor, right click on it, and select Edit myfun you get the error:

"myfun is a built-in, compiled, or inline function and cannot be edited"

It seems that doing so should produce the same behavior as typing edit myfun from the cli.

Prompted by this question on stackoverflow: https://stackoverflow.com/q/63325950/4183191

Steps to reproduce:
Step 1: Create the following script called myfunctiondefs.m

1;
function f1(); disp('hello from f1'); endfunction
function f2(); disp('hello from f2'); endfunction

Step 2: Create script myscript.m in the same directory

myfunctiondefs
f1()
f2()

Step 3: Open myscript.m in the octave GUI editor, run it once to generate the function definitions in the current session, and then highlight "f2" with the mouse, right-click, and select Edit f2 from the context menu.

Expected outcome: A generated f2.m file in the user's home folder, i.e. the same as what would have happened if one manually typed "edit f2.m" in the terminal.

Observed outcome:
 - In octave v5.1.0: A popup window saying "f2 is a built-in, compiled, or inline function and cannot be edited".

 - In octave v5.2.0: An empty, nameless m-file (in other words, a file called ".m" is created in the current directory).

Clearly there's a regression bug between v5.1.0 and v5.2.0.

However, the bigger question is, when a name in the GUI editor is a reference a command-line function, which doesn't right-clicking and selecting to edit it behave the same as the equivalent "edit" command?