[Remove 3Di Schematisation(s)] Shows a list of loaded schemations directly from the button. When user clicks it, the schematisation is removed from the QGIS project. Tooltip: "Remove 3Di Schematisation(s) from the current project".
[Switch active 3Di Schematisation] Shows a list of loaded schemations directly from the button. The active simulation has a ✓ symbol. When user clicks a schematisation, that schematisation become the active / editable one. Tooltip: Switch active (editable) 3Di Schematisation.
Four buttons with icons and the following tooltips: