How to make pg_dump skip extension?

This is on 9.3 but I can remember simillar things happening since 7.x. So I create database and install plpgsql extension into it. Later on I create a pg_dump and before restoring it into databse I make sure it also has plpgsql extension. Then when restoring this happens:

pg_restore: creating EXTENSION plpgsql
pg_restore: creating COMMENT EXTENSION plpgsql
pg_restore: [archiver (db)] Error while PROCESSING TOC:
pg_restore: [archiver (db)] Error from TOC entry 2053; 0 0 COMMENT EXTENSION plpgsql
pg_restore: [archiver (db)] could not execute query: ERROR:  must be owner of extension plpgsql
Command was: COMMENT ON EXTENSION plpgsql IS 'PL/pgSQL procedural language';

I'm creating a bunch of scripts and it's pretty important for me that pg_restore returns 0, so the fact that I can just ignore this isn't doing any good. What puzzles me is that IIRC I need to create extension as postgres master user, so I have no idea why all this EXTENSION stuff ends up in my dump. After all, I'm not owner of the language/extension?

Anyway, I'd be gratefull for any suggestion how to get rid of this. Please note, that I'm aware how the -l/-L switches work. This however seems to be way too much effort to correct just one simple extension comment.

For anyone looking for a workaround, limiting pg_restore to a specific schema has helped me get around this bug. See https://stackoverflow.com/a/11776053/11819

StackExchange Database Administrators Q#84798, answer score: 10