Copy text to clipboard

I have a PDF form, in which there's a button. When the user presses the button, I need to copy some text (an email address) to the clipboard, so that the user will be able to paste it in other applications. This text can be assumed to be constant (i.e. I can hardwire it in a JS).

I thought about creating a n invisible textfield in the form with the text, and the using selectNthPageWord and app.MenuItem("Copy"). But this works for only one word (an email address is processed as separate words), and also the clipboard seems to be erased once the JS finishes. I need the text to remain there.

Any help, please?