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I believe the "Show line numbers" setting should be common for all file types, since presumably the user's preference whether or not to see the line numbers, is the same when editing Java files and XML files.
Changing subcomponent to "setting"
This has been discussed in issue 22338. It is actually possible, altough not obvous -- just select multiple editors in Options dialog via Ctrl+click... *** This issue has been marked as a duplicate of 22338 ***