As you are asking in the Dev section, are you looking for a code change to compile your own version? As i’m not a developer, can’t help with that. It is probably possible to change the behavior of X button, or maybe just hide it and then instruct users to use File > Exit to close the app. Anyway, i will file a ticket to make an optional setting (not a default) to change the behavior, but as Spark lacks developers i can’t say when and whether it will be implemented. [SPARK-1942] Add an option to make Spark exit when pressing X button - IgniteRealtime JIRA