I can't get any JavaScript formatter settings to work (e.g. setting the tab policy to "Spaces only").
For JavaScript support there are two alternatives,
To configure the formatter used in the Generic Text Editor, see Angelo Zerr comment:
According this comment, try to
- create in your project root a
tsfmt.json
- fill this JSON file like https://github.com/vvakame/typescript-formatter#read-settings-from-files