I'm not sure exactly what is adding the '>>' to the sign column, but it appears to be there for anything from the quickfix window. Is there a way to clear the whole column without doing a funky :grep search (for soifjseofseogh for example).
The fastest way is probably to do:
:sign unplace *
You could set this up as a user defined :-command, or a mapping. For example, to make "
\u" trigger the command:
:nmap <silent> <leader>u :sign unplace *<CR>
However, what you describe is not default Vim behavior. You probably have a plugin that creates the signs whenever the Quickfix stuff is triggered. Take a look at the output of "
:scriptnames" and see if you can spot something that looks related.
In Vim 8, you can now also do
:set scl=no to hide the sign column forever (thanks to this answer on Stack Overflow for pointing this out).