repro case:
- set metamta.vary-subjects and metamta.re-prefix to false
- go to /settings/user/$ME/page/emailformat/ or /settings/builtin/global/page/emailformat/
expect:
- default values of Add "Re:" Prefix" and Vary Subjects to read Default: ($name_of_off_option)
actual:
- default values of those options read Default: ($name_of_on_option)