THIS^^^
And if you do get paid for your ideas/writing during the strike, that is considered scabbing and you will be barred from the WGA for life, as per this email from the Blacklist:
And, because a lot of people don’t understand this bit, this is about you selling your ideas or writing to US-based TV studios or movie studios who are part of the AMPTP. There is no strike against book publishers. Nor audiobooks, graphic novels, or poetry publishing. Or just writing.
Read the above from the WGA.