Text Format Miscellaneous Settings
Text Format > Misc
Insert spaces instead of tabs
When unmarked, pressing the Tab key inserts a tab character into the file. When marked, an appropriate number of spaces is inserted instead.
The Tab stop setting determines the interval between tab stops. Pressing the Tab key advances the cursor to the next tab stop.
Mark the Lines are independent checkbox when each line is an independent record and it is not useful to manipulate consecutive difference lines as a Section.
Mark the Column-based data checkbox when the position of each character on a line is important and lines should be compared column-by-column.