Inactive TreeView component after opening file

Hi,
I'm using TreeView components on a sheet for Drag&Drop, each component shows path to the file (after file is Drag-Dropped in it).
But there is one issue - just after file is opened those TreeViews are not "active" and can't be used.
I found workaround: scroll sheet after file is opened, like this

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Without this code I need to make some manual scrolling/activation on a sheet to make TreeView controls active.
Is there some better way to get my controls be ready to work just after file is opened?
I've commented scrolling code in attached workbook - to demostrate how it's working without it.
Any suggestions?

Nobody have no ideas? :-)