Hello, Org mode hackers,

Here is a recipe for a bug on the maint branch that causes a preset tag
filter to be carried over to another agenda view in some cases.

1. Change the load path setting in `setup.el'.

2. Start Emacs with `emacs -Q -l setup.el'.

3. Open a TODO list with `M-x org-agenda t'.

4. Move point to the TODO item with `C-s elisp RET'.

5. Evaluate the Elisp code link with `C-c C-o yes RET'.  This brings up
   a custom TODO list with the `foo' tag filtered.  This is a preset tag
   filter.  The TODO list is empty, as expected.

6. Return to the first TODO list with `M-x org-agenda t'.

7. Refresh it with `r'.  Now this TODO list is empty too and `{-foo}'
   appears in the mode line, indicating that the preset tag filter was
   carried over from one agenda view to another.

Best,

Thomas