(org-agenda-run-series): Remove any old agenda markers in the
buffer that is going to take the new block agenda.
(org-prepare-agenda): Reset markers before erasing the buffer anc
- running `org-agenda-mode', because after that hte local variable
+ running `org-agenda-mode', because after that the local variable
`org-agenda-markers' will have gone away.
(org-agenda-Quit):
(org-finalize-agenda): Install the marker resetter into the