private void adjustTableColumns() {
		bookmarkTable.sizeColumnsToFit(-1);
		TableColumn column =
			bookmarkTable.getColumn(bookmarkTable.getColumnName(BookmarkTableModel.COMMENT_COL));
		column.setPreferredWidth(200);
		column =
			bookmarkTable.getColumn(bookmarkTable.getColumnName(BookmarkTableModel.PREVIEW_COL));
		column.setPreferredWidth(150);
		column =
			bookmarkTable.getColumn(bookmarkTable.getColumnName(BookmarkTableModel.CATEGORY_COL));
		column.setPreferredWidth(90);
		column =
			bookmarkTable.getColumn(bookmarkTable.getColumnName(BookmarkTableModel.LOCATION_COL));
		column.setPreferredWidth(90);
	}
Size the columns such that the interesting ones are wider than the uninteresting columns.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/bookmark/BookmarkProvider.java