Add column to sort at the end when Ctrl+Click its header
When I click a header in the message list then ctrl-click a second header, the second header is sorted first. For example, if I have the following messages:
From | Subject PersonA | Hi! PersonB | Yo! PersonC | Dude, what's up? PersonB | Can you check this?
and then I click to sort by From, I get:
From v | Subject PersonA | Hi! PersonB | Yo! PersonB | Can you check this? PersonC | Dude, what's up?
and then I ctrl-click to sort by Subject, and get this:
From v | Subject v PersonB | Can you check this? PersonC | Dude, what's up? PersonA | Hi! PersonB | Yo!
It sorts by Subject first, even though I told it to sort by From first, then Subject. I would expect to see this:
From v | Subject v PersonA | Hi! PersonB | Can you check this? PersonB | Yo! PersonC | Dude, what's up?
which is sorted by From, then Subject. Instead, I have to click the headers in the opposite order: click Subject to get it to be the second sort, then ctrl-click From to get it as the first sort.