To ignore linenumber's selection in Less inside Screen

Answer 1

I think you want to select columns. That'd be much easier than a regex.

From the screen manpage:

   c or C to set the left or right margin respectively. If no
     repeat  count is  given,   both default  to the  current
     cursor position.
     Example: Try this on a  rather full text screen:  "C-a [
     M 20 l SPACE c 10 l 5 j C SPACE".

     This moves one  to the middle line of  the screen, moves
     in  20 columns left,  marks the  beginning of  the paste
     buffer, sets the left column, moves 5 columns down, sets
     the right  column, and then  marks the end of  the paste
     buffer. Now try:
     "C-a [ M 20 l SPACE 10 l 5 j SPACE"

     and notice the difference in the amount of text copied.

So, in your screenshot, press C-a [, move the cursor to the beginning of your text, press SPACE and then press c. Move to the end of your selection and then press SPACE again. Now you have the text you want.

Hope this wasn't too much info. You tagged it with beginner so I wasn't sure if you were a perl or screen beginner.