Transaction editor doesn't scroll when there are too many postings to fit in the dialog

[kpine]

If the transaction editor dialog height becomes too high because of many posting rows, the bottom postings and controls are effectively hidden.

This is usually not an issue, but I regularly encounter this with entries like paychecks, which have over 20 postings. Adding them via the UI isn't usable, even when the browser window is maximized on a 2560x1440 resolution desktop. The workaround is to zoom out the browser window, or use the editor.