libreadline dependency related Error while installing an app, “seedsync”

I was trying to install [Seedsync](https://github.com/ipsingh06/seedsync) . I followed the instructions on their github Download the deb package from the latest release Install the deb package: sudo dpkg -i When I try to install the deb package I get this error Selecting previously unselected package seedsync. (Reading database ... 276845 files and directories currently installed.) Preparing to unpack seedsync_0.6-0_amd64.deb ... Unpacking seedsync (0.6-0) ... dpkg: dependency problems prevent configuration of seedsync: seedsync depends on libreadline6 (>= 6.0); however: Package libreadline6 is not installed. dpkg: error processing package seedsync (--install): dependency problems - leaving unconfigured Processing triggers for libc-bin (2.27-3ubuntu1) ... Errors were encountered while processing: seedsync Trying to install libreadline6 tell me that it's either moved somewhere else or obsolete. **Edit:** sudo apt-get install libreadline6 gives me Reading package lists... Done Building dependency tree Reading state information... Done Package libreadline6 is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source E: Package 'libreadline6' has no installation candidate **Edit2:** Tring to install libc-bin or libreadline7 shows that it's already the newest version, 0 upgraded,0 newly installed and 0 not upgraded. The seedsync package asks for libreadline6 (>=6.0) and I think I have libreadline7 apt-get install libreadline7 Reading package lists... Done Building dependency tree Reading state information... Done libreadline7 is already the newest version (7.0-3). 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.