Popup warning to leave page even though no changes have been made

Hi!

When activating the plugin, every time I try to leave the Contact Form 7 Page I get a popup saying that:

“Do you want to leave this site? Changes you made may not be saved.”

If I leave, things still work, and the changes I’ve already made and saved with the update button is still there, so this is an unnecessary warning, looks like a bug.

The message disappears as soon as I deactivate the plugin.

https://wordpress.org/plugins/cf7-conditional-fields/