Tags: patch
Severity: wishlist

For a long time after announcing this feature in
https://lists.gnu.org/archive/html/emacs-devel/2018-08/msg00537.html
I received requests in private mails asking when I'll submit a complete patch.
I'm sorry, it took much time addressing all concerns raised in that thread,
and testing in many possible scenarios.  Based on the feedback, I rewrote it
several times, and now finally it's optimized to be fast and reliable.