Every time when I run Dropbox next message appear 
'python-gpgme' package was interface to the gpgme before Ubuntu 17.10. From Ubuntu 17.10 (up to present) 'python-gpgme' is deprecated in favor of 'python-gpg' ('python3-gpg' for python 3). Currently 'python-gpgme' is no more in Ubuntu repositories!
Probably this is small mistake (forgotten package name) need to be corrected. Everything else works. Please forward the bug note to your technical team. This ****** message is really annoying and the checkbox 'Don't show this again' don't work.
Thanks in advance.