When editing a file in PhpStorm, it generates a file named FILENAME.js___jb_tmp___ (where FILENAME is the name of the file).
How can I turn this off?
This is a result of using "Safe write" - changes are not written directly to original file but to temporary one instead, which is renamed and replaces original file when save operation is completed successfully. You can turn it off in Settings (Preferences) | Appearance & Behavior | System Settings, Use "safe writes".