"Could not open X display" while installing insync rpm

Bugs and issues Linux
#1

When I install insync I get the following message:

Additional rpm output:

** (zenity:27487): WARNING **: Could not open X display
No protocol specified

** (zenity:27489): WARNING **: Could not open X display
Unable to init server: Could not connect: Connection refused

(zenity:27487): Gtk-WARNING **: cannot open display: :
No protocol specified
Unable to init server: Could not connect: Connection refused

(zenity:27489): Gtk-WARNING **: cannot open display: :2
Unknown media type in type 'all/all'
Unknown media type in type 'all/allfiles'
Insync installation has finished. You may now start it.
#2

@cesarizu Those should be harmless warnings. Insync tries to use zenity to notify you that the installation has finished, but there seems to be an issue with it. Does it prevent Insync from installing?

#3

After a couple of year this is still happening. No package should try to notify the user that it finished installing by itself. If the user is using a graphical package manager, the package manager would (or would not) notify the user. But imagine if every package tries to do that, it would be a disaster trying to update a Linux installation.