I grew up listening to recordings of "Round the Horne" in the UK, which included two characters Julian & Sandy that chatted a little in Polari during their sketches. A bunch of Polari words and phrases have migrated into general UK slang — so it's not really a case of dying out… more migrating and changing — as languages & dialects often do.
I'm always astonished as to hows fresh Round the Horne sounds even today, when many of the comedy programmes of that era sound distinctly dated. Still funny, worth a listen.
As I'm sure you know but others might not, that's not a "real" Julian and Sandy sketch.
Edit: The classic Julian and Sandy sketches were recorded between 1965 and 1968. The last one was a reunion in 1987, shortly before Kenneth Williams' death.
Ian McDonald's Everness series has main characters speaking in Polari, and where I first encountered it as a thing. And the books, even though they're aimed at young adults are really good.
What surprised me is how many words I use regualrly had their origins in Polari. I don't know whether it's because they've made their way into mainstream language, or just a regional thing though.
There is a similar phenomenon in American English where a huge, huge number of words in the dominant dialects come directly from AAVE (Afro-American Vernacular English). I would not be surprised if many of those words have spread all throughout the anglophonic world.
Trolling in Polari has a different origin from its usage in reference to the internet, where the term has its origin in alt.folklore.urban. The Polari term is still used in the gay scene (it refers to loitering around a known cottaging location hoping to meet someone).
Trawling and trolling are different fishing techniques. Trawling involves hanging a big net off the back of a boat to scoop up all the fish along a large swath of water, whereas trolling involves hanging one or more baited lines off the back of a boat, with the boat’s slow movement enticing fish to bite.
The circuses were dominated by Italian families, and probably some of the fairgrounds also, but what's the connection between circuses / fairgrounds and theaters?
I grew up listening to recordings of "Round the Horne" in the UK, which included two characters Julian & Sandy that chatted a little in Polari during their sketches. A bunch of Polari words and phrases have migrated into general UK slang — so it's not really a case of dying out… more migrating and changing — as languages & dialects often do.