The application Synapse has closed unexpectedly

This morning when i open synapse and then i click on something, synapse just went crazy, it's showing error 'The application Synapse has closed unexpectedly'. I have no idea what's going on.

Normally when you open synapse and then you click on something else, synapse will close but this time not only close but it's showing error message as well. But this only happens one time so far, now synapse is back to normal.

Here's the error detail, i'm using ubuntu 16.04 xenial by the way, despite this error, it won't stop me from using synapse, i still think synapse is very cool program.