At some point, the optional argument LOCAL was added to org-capture-get:
(org-capture-get PROP &optional LOCAL) "When LOCAL is set, use the local variable ‘org-capture-current-plist’, this is necessary after initialization of the capture process, to avoid conflicts with other active capture processes." A lot of the org-capture-get calls in org-capture.el do not set LOCAL and suffer from aforementioned conflicts. The calls inside function org-capture are exempt from this, but the calls inside org-capture-finalize that do not set LOCAL are obviously erroneous. There are more org-capture-get calls in other functions that have to be reviewed. Emacs : GNU Emacs 25.3.2 (x86_64-apple-darwin17.4.0, Carbon Version 158 AppKit 1561.2) of 2018-02-19 Package: Org mode version 9.2 (release_9.2 @ /Users/xristos/code/elisp/third-party/org-mode/lisp/)