"Last viewed" Error

There is an Last viewed List in Dynamics:

There is functionality to fix elements in it (As you can see on screenshot there are 4 elements fixed).

But there is an issue:

When some time (i don't know now, how many time) pass, this elements will disappear from this list.

2 questions:

1. Did Somebody meet this issue?

2. Is it some receipt to fix it?