Mapping for <leader>b?

[lucassperez]

Hello, I recently installed this plugin and it is working very nicely for leading white spaces, very cool! But the problem is that when I installed it, I started getting an error with my <leader>b mapping. Vim says:

E464: Ambiguous use of user-defined command

I uninstalled every plugin I use except indentLine and I got this error. I also tested installing every single one of them except indentLine and I didn't got any error, so I'm guessing this plugin maps <leader>b to something?
I'm probably missing something, but I couldn't find it in the docs. Also, when I have only indentLine installed, the <leader>b command doesn't raise errors but doesn't appear to do anything, too.
I would like to keep my user-defined command, how can I disable the plugin's mapping, assuming it actually has one?

Thanks.

EDIT
Okay, I remapped my <leader>b to something else and aparently the problem is not the sequence, it is the command itself.
I was mapping <leader>b to :Le<CR> (open file explorer). When I have indentLine installed, even if I type :Le by hand I get this error.