Warnings with axlSetFindFilter(?onButtons '("BONDSMART" "DYNTHEMALS" "INVISIBLE"))

Using 17.2S051.

I've adjusted the Find Filter many times but not seen this issue before. I'm not sure what I'm doing wrong but clearly something is borked.

I'm saving the Find Filter at the start of my program and then restoring it at the end. Typical stuff. But in this program I see the following in the console:

*WARNING* (axlSetFindFilter): Options are ignored for onButtons - "BONDSMART"
*WARNING* (axlSetFindFilter): Options are ignored for onButtons - "DYNTHEMALS"
*WARNING* (axlSetFindFilter): Options are ignored for onButtons - "INVISIBLE"

I'm using the typical method:

procedure(<function name>(<parameter(s)>)
let((...)
; save find filter
lt_enabled = axlGetFindFilter(t)
lt_onButtons = axlGetFindFilter(nil)

; allowing selecting only text; adding "invisible" applies for all layers so the entire board is updated
axlSetFindFilter(?enabled list("noall" "invisible" "text") ?onButtons list("noall" "text"))
;axlMsgPut("%L" lt_enabled)
;axlMsgPut("%L" lt_onButtons)

<do stuff...>

axlSetFindFilter(?enabled lt_enabled ?onButtons lt_onButtons) ; restore find filter

<return value>
)
)

I can see that the lt_onButtons variable in the function above contains the three offending values in addition to "SYMBOLS". Those items aren't in the UI so I'm not sure why they're being returned to me. Even moreso because I always get back those four items in a list, regardless of how I configure the Find Filter before running my function. Even if I uncheck all items in the Find Filter I still get those four elements returned to me. I do see only "Text enabled and checked so that part works, it's only the restoration of the Find Filter that is a problem (it is not restored now and stays with only "Text" enabled and checked).

While I could use member(), or one if it's related functions, to strip out the problematic list elements that's hacky and not future-proof. I don't get why lt_onButtons returns elements that have no checkbox.

I can run different functions I've written on the same board and only this function results in the warnings above so I'm quite sure it's me and I'm just not seeing my own problem. Other functions where I've adjusted the Find Filter do not give any warnings and, as far as I can see, properly restore the Find Filter settings. Oddly, I see "nil" for both lt_enabled and lt_onButtons when I print them to the console using axlMsgPut() in working functions but the Find Filter is properly restored so I've done it right (I guess?).

Other board files have exactly the same behavior, where this one function is giving me the same returned list regardless of Find Filter settings while the other functions work fine and return nil as mentioned above. So I don't think it has anything to do with the board file.

Any ideas what I'm doing wrong?