Thanks, now the hotkey resets thumbnail browser. But a new behavior with this version is resetting doesn't return focus to "All" item at the top. It's rather a strange state. No item either from thumbnail browser or from main panel is selected, but the node somehow remembers the previously selected thumbnail browser item and keeps going back to the position when switching back from another node.
If I run the hotkey from column browser, focus returns to the "All" item at the top of the column as expected. I'd expect the same behavior for thumbnail browser, but it doesn't work that way.