org-id users: You will need to set org-id-extra-files correctly when using Org 9.3+

[kaushalmodi]

This has come up in quite a few issues. So I am documenting this here in case someone is confused why the Org ID file locations used to be found correctly at some point, and not any more.

The behavior with "auto Org ID destination detection" changed in this commit https://git.savannah.gnu.org/cgit/emacs/org-mode.git/commit/?id=9865e6bd8be65229be4eac4f459f62e47fab2be7 which became part of Org 9.3.0.

> git describe --tags 9865e6bd8be65229be4eac4f459f62e47fab2be7
release_9.2.5-422-g9865e6bd8

The key change was this inside org-id-update-id-locations:

Earlier, org-id-update-id-locations used to auto-add all the open Org buffers to the list of files to be searched for IDs. But after commit 9865e6b8d or Org 9.3.0, that doesn't happen any more.

Fix

The fix is to run this snippet in the directory from which you want to add all the Org files for ID search:

(setq org-id-extra-files (directory-files-recursively default-directory "\.org$"))