Just to confirm that the Plug-in is disabled by the official Sierra release: “Contact the makers of these plug-ins for versions that are compatible with Mail 10.0”
Yes, remains the same. was hoping for an update today with Sierra coming out. Hopefully tomorrow.
Just to follow up in this thread, Christian has announced that a version supporting Sierra is currently in beta, and should be out later this month.
UGH! would be my reply on the delay.
There are more issues than the Mail plugin at hand. As it has been since Mavericks release, the QA from Apple appears to not have improved (especially concerning Mail). Also, the have made some big changes under-the-hood that are affecting more than just our apps.
PS: You should still be able to drag and drop from Apple Mail to DEVONthink.
Yep… heard SnapScan wasn’t prepared with their app. I do drag, but it still takes forever compared. Lots of spinning for some reason.
And more than they have been affected by changes to the PDFKit and text frameworks. 
What is a good way to drag and drop Mail in to DTPO?
I just dragged it to the Devonthing symbol in my dock, told it in what group I wanted it as with all normal files but are just getting a Bookmark.
Bookmark works fine but I have no way of knowing what the mail is all bout.
Just a long text saying: message:%C and so on.
The Dock is only useful for real files/folders, otherwise the results might be unexpected as the Dock’s drag & drop support is kind of weird & limited. Therefore the best workflow is to drag & drop the emails to a window of DEVONthink or to the Sorter.
Thanks! Works like a dream.
Mail plug-in now works perfect with latest update!
Thanks DevonThink.
With 2.9.5 first the mail import works now perfect, but after one day it stops working …
Do I have to remove an old file?
I don´t think so, mine has worked every day since I installed it after the download.
Just try to Install Plugins again inside Devonthink. However I don´t think all versions of DT can import mails, I have the DevonThink Pro Office version.