Hello, I'm exporting a letter without a to-address, and it generates a spurious "mbox" in the letter. I found that if I change line 708 of ox-koma-letter.el from "\\\\mbox{}" to "\\mbox{}" the problem goes away. Is this a (known) bug? Thanks, Alan -- OpenPGP Key ID : 040D0A3B4ED2E5C7 Monthly Athmospheric CO₂, Mauna Loa Obs. 2017-09: 403.38, 2016-09: 401.03