Resize file name column in Safari OPEN FILE dialog box

When I need to attach a file to a website submission in Safari, I have to use Safari's dialog box for opening files. This opens a roughly 10 inch wide dialog window on my screen, but only about 2 inches are used. The other 10 inches are not used for anything. The only 2 inches that are really used is the second column which displays the contents of the folder I am looking in. Because the column is only 2 inches wide, I cannot see the file names. Instead, I can only see the first few characters and last few characters of the file name, which are virtually identical for the files that are present in the folder. Thus, in order to find a particular file I have to click on each individual file and look at what shows up in the "preview" panel. This is insanely counterproductive. How can I resize the column that shows the file names so I can actually see the file names and use the file names to differentiate one file from another?