I'm starting to vaguely feel like I don't know Solidworks at all anymore!
When you open a part (or assembly) with multiple configurations but for which you are not the designer. How do you know which function/dimension influences the different configurations? Is there a summary table?
You can find the room family table in the configurations (and edit it):
And/or see the piloted ribs that change color as well
This color code is applied according to the system options, Colors, Dimensions controlled by the part family (here controlled ribs in magenta)
Thank you @sbadenis
Of course, with the luck I have, it works if the person has made a family table and not "normal" configurations? 
If normal config no different color but by clicking on a coast, you can see if it is identical in all configs or not:
Example with driver all configurations:
Example with single config driver:
If necessary you can always add a room family table from the existing configs.
Insert, Table, Room Family and then switch to Automatic mode.
If you're afraid of doing stupid things, save your piece on your hard drive first.
Edit: impossible to see if use in one or more configs, as soon as one coast is modified, the others also pass with the same symbol. Add a table if you want to check.
I'm right-clicking on a function, configure the function.
In the panel that appears, there is an icon at the bottom left that allows you to display all the configured functions and dimensions (in principle)
