Bug: When deleting highlighted records in Selected View, all selected records get deleted
When highlighting a subset of records in Selected View and pressing 'Delete' in edit mode, all selected records get deleted.
The Map View has focus, when the table requires focus to delete only highlighted records.
Use the keyboard shortcut to start editing, not the editor toolbar:
Open the Attribute Table of the layer.
Select a set of records to work with and switch to Selected View.
Highlight a subset of records to delete.
Use the keyboard shortcut SHIFT + CTRL + E to start editing in the table.
Press 'Delete' on the keyboard.
This deletes only the highlighted records as expected.
If this bug has occurred because editing was started from the toolbar, that is because the Delete key was pressed before the Attribute Table regained focus. If editing is started from the toolbar, the attribute table first needs to gain focus by clicking on the attribute table dialog box before deletion of highlighted records can occur.