Might as well post my present issue, just in case anyone has a simple solution.
OS: Ubuntu 16.04.2 LTS 64-bit.
Application: Kodi v18.0 (also tried v17)
Issue: After running my latest batch of system updates and removing unused packages, Kodi freezes and stops responding or terminates suddenly every time I attempt to access or install any add-ons. Default YouTube addon pops up a failure to connect message when the application first opens. All attempts to install any add-ons cause the application to terminate.
Crashlog:
Troubleshooting: Removed all packages, uninstalled, reinstalled v17 via terminal. Issue persists.