我读了下less的man文档，光option就很长，一条一条看，有几点没弄明白：

1.

--old-bot, Reverts to the old bottom of screen behavior. This can be sometimes desirable if the long lines are not wrapped correctly when reaching the bottom of the terminal, while scrolling forward.

这个option是用来干什么的？old bottom of screen behavior是个什么东西？

2.

-jn or --jump-target=n, Specifies a line on the screen where the "target" line is to be positioned. The target line is the line specified by any command to search for a pattern, jump to a line number, jump to a file percentage or jump to a tag.

关于这个option，这里的target line是表示什么？这个option是用来干嘛的？我们一般什么时候会用到？