[O] element-debug-mode breaks capture

[Samuel Wales]

in maint when i capture, i often get this:

  Error running timer `org-element--cache-sync': (wrong-type-argument
integer-or-marker-p nil)

so i run element-debug-mode on the base buffer of the
capture.  but then capture stops working:

Debugger entered--Lisp error: (error "Capture abort:
(wrong-type-argument keymapp nil)")

capture is being called with nil argument.

user error?