Copy Master Detail - Table Not Showing in Options

Are you in App Management?  Or App Properties.  You need to be in App Management.  (At the Application level, not table level)

In App management from the application settings, not table settings

Just a guess.  Do you have at least two tables and is there a relationship between them?

yep, what is weird is I see the table  I want to create a copy button for on a  copy of the application, just not in the original application.

OK, now I understand your question.  Are you saying that you want to create a button where the source table is not the App you are in?

no my bad, sorry i am making things confusing.

1. I go into App settings and select App Management
2. I select Copy Master Detail 
3. I go to the table dropdown to choose which table I want to make the copy button for
4. wait..what..the table i want isn't in the dropdown option? huh?

But..

If I create a copy of the whole application, do the same steps above in the copied application, the table i want IS in the dropdown list?

weird eh?

I cannot explain why it would work with A Copy.

But the whole Copy Master Detail is finicky if you have what are called looping relationships or also that seems to include relationships built for conditional dropdown purposes.   My theory would be that the system is only seeing one child table and it is not valid for making the button so it does not offer that parent table.

You may need to got to support on this one as it is hard to diagnose without being in your app.

Today I ran into an issue; which resulted in making sure the following was included in the copyMasterDetail button "&recurse=false".

In my case this was critical to ensure that I could create a set of records in a child table from either parent-tables.