It is not obvious where arrow keys navigate to (column mode)

Lets say that I have highlighted one of the default folders in the sidebar, and then I press the right arrow key → with the intention of entering into keyboard navigation in that folder. There is no visual indication that I have done this, but I can then press the down arrow ↓ and it is then apparent where I am. The same is true within columns. Pressing the right arrow into a folder does not give any visual indication that my arrow key navigation _is now constrained to that subfolder_. In macOS Finder, there is always an indicator. This issue is probably related to #690

Thank you for reading and for your consideration of the issue.

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