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I vaguely remember a website that was helpful in a previous life that could narrow down choices. I don't remember it looking like the below but seems like it does the same thing! https://www.tuc.org.uk/join-union
Regardless of anything else going on, wearing a t-shirt that says that, IS provocative and could definitely be seen as offensive. As a member of an LGBT committee, you'd expect more inclusivity.
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