I'm unable to reduce the size of the columns in the Data tab of a table: neither the Right-click -> Auto-fit options nor manual drag of the right header border work.
Also scrolling through data is impractical (compared to V3.2.09): keyboard PgUp and PgDown don't work and, if I use the scroll bar, data display keeps returning to row #1 until ALL rows are fetched.
SQLDev 184.108.40.206.27, Java 1.7.0_21, Mac OS X 10.8.4.
I just re-checked: the problem is that both dragging and auto-fitting work IF you have more columns than can fit on screen. Otherwise neither is working properly: no matter what you do, SQLDev will always arrange the colums to fill the whole viewport. Perhaps this behaviour was intended as a feature? I personally find it confusing.