I would like to be able to change the positions of the columns in the file open dialogue. I know of feature request https://sourceforge.net/p/jedit/feature-requests/40/ but I am not sure whether this is a duplicate and I was not able to find the bug report mentioned there.
Fixed in revision 23970. Note this fix only addresses moving the columns. The older #40 request also wanted to be able to hide columns, that is not implemented in this fix.