v-clipboard's copy function fails while using cypress

[Daffodil404]

When I was using cypress to run test cases for the purpose to copy text via v-clipboard , it always occurs error while copying
here is the simple example of my problem
template part:
<Button id="testBtn" v-clipboard:copy="statement" v-clipboard:success="handleCopySuccess" v-clipboard:error="handleCopyError"/>
Button is a component whose core is <button> , which is used to control the process via click it.
cypress test part
cy.get('#testBtn').click()
after execute this command , there is always a fail message for us that the copy had been failed, and there was nothing in the clipboard.
What should I do to copy correctly while in cypress