It's a moniker for the 4chan board /lgbt/. The name comes from "To tell the truth," namely due to the reputation of trans 4chan users to be very harsh to one another.

that's a backronym at best

the original joke was that despite being called /LGBT/ like 80 percent of all threads were about trans topics for a while at the start, with wlw and mlm general threads kinda on the side

so "trans trans trans trans"

For those watching at home: being harsh is not the same thing as being truthful.

4chan place