Aaron Zeng <me@bcc32.com> writes:

> (I'm running org mode from the Spacemacs org layer, which includes the
> org-plus-contrib package).
>
> Reproduction:
> 1. Create a new entry "* TODO Temp"
> 2. Clock in under that entry
> 3. Cancel the clock
> 4. [M-x describe-variable org-clock-current-task] is still set to
> "Temp" instead of being nil, which is what I expected.
> 5. In Spacemacs with the spaceline-all-the-icons mode line, "Temp"
> still appears in the "currently clocked task" position.
>
> Emacs  : GNU Emacs 26.2 (build 1, x86_64-w64-mingw32)
>  of 2019-04-13
> Package: Org mode version 9.2.3 (9.2.3-23-g967801-elpaplus @
> <snip>/.emacs.d/elpa/26.2/develop/org-plus-contrib-20190603/)

Following your steps on commit 967801 (which matches your version
output), I'm unable to trigger the issue (i.e. org-clock-current-task is
nil following 3).

If you try with a vanilla configuration and Org loaded, do you still see
the issue?  Perhaps there's an interaction with a configuration value.

--
Kyle