Resizing FILL columns

Hi! Dear DOpus devs!
When a column is set to FILL or COLLAPSE mode, its not possible to resize that column. If it is set as AUTO or EXPAND, it is possible. I mostly use FILL column setting for the name col. But if a filename is too long still, i have to go and set it to AUTO or a number, then adjust the size. Could it be possible to make FILL columns resizable by grabbing the edge with the mouse?
Thank you!

You can quickly toggle auto-size mode using this:

More discussion here: