I'm sure that this poster was discussed on Mumsnet but, when I searched for the phrase just now in FWR, this was the only thread it appeared in. Maybe the old threads or posts were deleted?
I'm resurrecting this old thread rather than starting a new one because I was looking for the source too.
I think it is in this "Gender Unicorn and LGBTQ+ Youth Allies" tweet by, ironically, "Inspiring Women in Leadership Scotland" on 4 Feb 2020:
Delighted 2 share @rachel_brian illustration post regarding the LGBT community. Be curious, respectful, listen & learn. Ask questions like- 'What pronouns do you use?' & provide resources like the 'Gender Unicorn' 2 help people understand their gender expression #LGBTHM2020
https://twitter.com/IWiLScot_/status/1224668894096433153
Archived thread - in which IWILScot double down: https://archive.ph/Ixx8b
"We believe that 'embracing discomfort' is relating to stepping into conversations, not out of them, when speaking about LGBTQ and other topics in this illustration #LGBTHM2020"
"We believe that having courageous conversations with others, as uncomfortable as it may be, will help us to work towards our vision for fair and inclusive world #LGBTHM2020"
They also linking to a "Resources" page by those totally sane individuals who are well-funded by the Scottish Government: Scottish Trans, which seems to have moved here:
https://www.scottishtrans.org/resource/all-resources/
2020 version archived: https://archive.is/RKUpQ
saying, "We hope the link below can answer some of your questions in more detail. There are many organisations that support trans people, which have very useful resources"
I found the IWLScot tweet embedded in this post on Ophelia Benson's blog, "Butterflies and Wheels"
Embrace discomfort (or we’ll force it on you)
5 Feb 2020
https://www.butterfliesandwheels.org/2020/embrace-discomfort-or-well-force-it-on-you/
Archived: https://archive.ph/RXgHw
Rachel Brian, who produced the illustration is, also ironically, Founder & CEO of Blue Seat Studios who created "Consent, it's Simple as Tea"
https://www.blueseatstudios.com/
Tea Consent
2015
and
Consent for Kids
Rachel is an author with Hachett and went on to write "Respect", aimed at children aged 7+
A Q&A with Rachel Brian on her new book, Respect
https://www.lovereading4kids.co.uk/school-blog/a-q-a-with-rachel-brian-on-her-new-book-respect-6040
Consent. Respect. But when it comes to being a Trans Ally: Submit and "Embrace Discomfort".
It's the usual Intersectional, Pyramid of Power, Privilege and Oppression bollocks.
Looking up "Embrace Discomfort" it seems to crop up a lot in US discourse about race and "white privilege", with black, male cross-dressers being the ultimate arbiters of truth and wisdom, of course.