Signal is a great encrypted communications application built upon Electron framework. Couple of months ago I faced the issue that Signal had failed to start showing a message like this: “Uncaught Exception: Error: /tmp/.org.chromium.Chromium.j4ITUv: failed to map segment from shared object”.
Here is the solution.
The article describes a few pitfalls I encountered when trying to upgrade from Ubuntu 16.04.5 (LTS) to Ubuntu 18.04.1 (LTS) and possible solutions.
After upgrade from the latest Ubuntu 16.04 LTS to Ubuntu 18.04.1 LTS, the server refused to reboot. I had to use IPMI to connect to the otherwise unresponsive server and reboot it forcefully. I probably should have used sync; reboot