Normally, collapsing and expanding a node doesn't change the collapse status of the child nodes in the tab tree. This doesn't work when a node is collapsed before Falkon is shut down and then expanded after Falkon has been started again: in the restored session, the child nodes are all expanded now.
Git commit bc26e9377ca8d22e81c9234e4f876d204d50ab24 by David Rosca. Committed on 29/04/2018 at 10:52. Pushed by drosca into branch 'Falkon/3.0'. VerticalTabs: Preserve exapnded state of items inside collapsed parent FIXED-IN: 3.0.1 M +8 -8 src/plugins/VerticalTabs/tabtreeview.cpp https://commits.kde.org/falkon/bc26e9377ca8d22e81c9234e4f876d204d50ab24