This worked in FileMaker 16.
In version 17, if you open the Data Viewer, then move your mouse to the column headers and then to the column divider lines, it used to change the cursor and allow you to resize the columns in the Data Viewer. This no longer works.
The Data Viewer is now nearly worthless to me. I have a lot of variables defined, and the prefixes on my variable names overlap since I use descriptive names for my variables. I can double click on the variable names to see them in a dialog, but then I'll go Click crazy.
NOT to mention that I cannot submit a simple bug report to FileMaker and I need to go through this forum.
This is on the Mac under MacOS 10.13.4, using FileMaker Advanced Pro 18.104.22.168.