It connects the FunctionTreeView to the data table, and same with the check box above the FunctionTreeView. The following is now possible:

    Selecting individual or multiple datasets, and then add or remove functions to the FunctionTreeView for only these datasets by unticking the tick box.
    Add or remove functions to all datasets by ticking the checkbox.
    Selecting between datasets will display the functions related to that dataset.
    Switching between Sequential and Simultaneous fitting will hide/show the global parameter column and multi domain index

It is also now possible to do the following:

    Editing parameter and attribute values
    Local and global ties
    constraints
    global parameters