When executing a statement the contents of the editor is put into an internal buffer together with the information about the text selection and the cursor position.Even when you select a part of the current text and execute that statement, the whole text is stored in the history buffer together with the selection information.
See the description of the alternate delimiter for details. for stored procedures) that contain semicolons that should not delimit the statements.
As long as at least one statement is running the title of the main window will be prefixed with the » sign.
Every window in SQL Workbench/J can be resized and will remember its size.
So in case not everything is readable on a dialog, just resize the window so that the missing parts become visible, and that size will be kept for the future. The "current" statement will be the text between the next delimiter before the current cursor position and the delimiter after the cursor position.
Example (| indicating the cursor position) statement.