Package: thunderbird Version: 1:45.6.0-3 After upgrading from Icedove to Thunderbird, I found that /etc/icedove directory is not removed. Here is what is left there:
$ ls -laR /etc/icedove /etc/icedove: total 20 drwxr-xr-x 3 root root 4096 Feb 15 18:09 . drwxr-xr-x 144 root root 12288 Feb 15 18:09 .. drwxr-xr-x 2 root root 4096 Sep 12 2011 profile /etc/icedove/profile: total 8 drwxr-xr-x 2 root root 4096 Sep 12 2011 . drwxr-xr-x 3 root root 4096 Feb 15 18:09 ..
The /etc/icedove/profile directory is probably left by an older version of icedove package, and should be removed.