Mac: Strange behavior of Reminder in Note Stacks

[Dave Land 14]

Hello,

I use reminders to "Pin" certain notes to the top of the note list in the 2nd column of the Mac desktop app.

Mostly, it works fine, but it seems that reminders in some notebooks disappear when viewing the note stack that contains them.

To save screen space at the top of the list, I thought I'd consolidate notes into one notebook, because the notebook headers take up so much room.

Wasted header space boxed red. Reminder I intend to move boxed green. Total number of "pinned" notes (5 Reminders) circled yellow:

When I moved a reminder note from a "Clients" notebook to a "References" notebook, it shows up just fine when viewing the "References" notebook, as pictured below.

Unfortunately, viewing a single notebook wastes space with a giant "+ Add a reminder to Referen…" link, so it's kind of a wash in terms of column space.

But note that the number of reminders remains 5—my "Client Links & Status" reminder is present in this notebook:

When I view the stack that contains the "References" notebook, the "Client Links & Status" reminder vanishes.

Note that the header now says that there are only 4 reminders, even though we just saw that there are 5 reminders in "References":

At first, I thought there was maybe a limit of four reminders per notebook in the stack view, but I created a new reminder in "References" and it appeared just fine in the stack view.

Any wisdom from this august body of experts?