can't do Find/Search on LC UI stacks (bug?) [was "script for redo/undo text?"]

[Nicolas Cueto]

"Find and Replace" is warning me that "... To search a LiveCode UI stack
you must first select 'Show IDE Stacks in Lists' from the View menu."  But,
I did select "Show IDE Stacks" in "View"!

Something I've overlooked or a bug?

The reason I want to search LC UI stacks? To understand Mark Wieder's
stack/suggestion on how to do "undo/redo" (thank you, Mark!), it seems I
have to dig there for functions and such.

Thank you.

--
Nicolas Cueto