Lambda that uses INDEX with array arguments behaves inconsistently when saved in the Name Manager

not sure why this is happening but I was able to confirm and get this image of the desktop application on the left and the online version on the right of the exact same file showing the difference in results:

a couple other things of interest include the Excel Labs tool showing in both cases the correct answer and even identifying on the web version that it's answer doesn't match the result shown on the grid.  

Also hovering on the indx function (which is the lambda function) on the web version is showing a #CALC! error.  Although I would point to this as a place to start I will also note that if I highlight the indx function on the desktop it shows a result of 1 instead of the expected {1,2,4} so that isn't correct on the desktop either.

as a workaround I was able to break INDEX into a combination of CHOOSECOLS(CHOOSEROWS()) and that worked:

=LAMBDA(arr,CHOOSECOLS(CHOOSEROWS(arr,{1}),{1,2,4}))

Interesting the hover over on the web version still says #CALC! but now hover over on the app does correctly say {1,2,4}