Display & export meta columns

Flamingo currently displays Subject, From, Channel and Date in the list of Inbound Messages, and that’s not enough to quickly find and export certain messages. It would be good to allow additional columns, such as the post name, which is captured in the form meta data.

Similarly, the export only contains data entered on the form itself, but it would be great to have the form meta data as well for further offline analysis.

Unfortunately, I can’t add my vote to https://github.com/takayukister/flamingo/issues/3, so hopefully, this will count as a vote + additional suggestion.