I have deleted ScriptLog.log file from ThingworxStorage/Logs/ and now I don´t have script logs in Composer.
I tried creating the file, adding tomcat8.5 user and group owner but no luck.
I have ThingWorx 8.3.1-b441 installed on Ubuntu 16.04 with PostgreSQL and Tomcat.
Go to Solution.
I have disabled Enable Script Stack Tracing in Configuration on LoggingSubsystem and then I restarted the server.