Reduce of empty array with no initial value error on Scroll


I'm currently having strange error on my console when scrolling the page on mobile app:
Uncaught TypeError: Reduce of empty array with no initial value
    at Array.reduce (<anonymous>)
    at t.getCurrentScrollViewerState (virtualized-scroll-viewer.js:708)
    at virtualized-scroll-viewer.js:399

I'm a bit confused with it. Any suggestions of how to identify source of the problem are welcomed.



Hi Mykola,

Never encountered this error. Being a JavaScript error and by the place and trigger, it is something that is happening in automatic generated code.

What do you have in this screen?


Hi Eduardo,

There are lots of things on that screen including tabs and lists. But I've noticed that this error only happens if I start scrolling while the page is not fully loaded (some data for lists is still be fetching). If I wait till all is done - no error.



This is interesting.
Seems like a bad "interaction" that is not being taking into account by the automatic code.

If it is this, it would be a bug.

I would open a ticket with support, sending them a small test app that can reproduce the problem.


Hi, may i know is any finding for this? i encounter same problem in Outsystems 11. 

We were experiencing the same issue  (on a screen with accordion items in a list) and were able to solve it by setting disable-virtualization = True on the list 

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