menu - When to use ellipses with ToolStripMenuItem Navigation

I have been tasked with standardising the menu systems on our product.

At the moment some of the menu items have ellipses some do not.

When would it be appropriate to display ellipses at the end of a menu item?

I can't seem to find any opinions on the internet, nor can I find any sort of guidance.

Even looking at the menu on Firefox I can't seem to see why sometimes there are ellipses and other times there are not.

For Firefox the "File Menu" looks as follows:

• New Tab


• New Window


• New Private Window


• Open File... (note the ellipses)


• Save Page As...


• Email Link...


• Page Setup...


• Print Preview (and now no ellipses)



• Print... (and back again)


• Work Offline


• Exit

Any guidance would be very much appreciated. (Even opinion based at this stage)

Answer

I believe the "..." is used on actions that will require additional user input to complete the flow, where the items w/o it will take you to the end result right away.

Example:

1. Open File... - you will then have to select the file



2. Save Page As... - you will have to specify the name, etc


3. New Window - you will end up with a new Window opened

... and so on.