Created attachment 3270 Proposed patch Hi, Xfce4-mailwatch-plugin uses some functions from libgcrypt, without explicitly linking against it, which makes the linking fails with stricter linkers such as binutils-gold. The attached patch works for me (I'm not an autotools guru, so it can surely be improved). FWIW, I generated it after applying the 4.7 panel patch described in Bug #6608. Thanks!
Created attachment 3271 fixed version (the previous version had some spurious headers, sorry)
Fixed.