I didn't even think about the racist meaning of "Troll" when replying to someone who was Trolling my forum. I remember some Shadowrun Glossaries, but I'm trying to come up with some "in period" slander that I could use to describe the current day Internet Troll in the 2060's trix...
I suspect that trolling would still be around in the 6th world--at least for us old timers.
UGE only started for elves and dwarves in 2011 (this year) and magic wasn't strong enough to change orks and trolls until 2021. So trolling, as an expression has another 10 years to set itself into the collective conscious.
For the younger set I would probably use drekking forums--or see what your PCs come up with. You can use the here and now on the usage of gay for a template.
And it is a completely different "trolling" that is going on--with more do to with fishing than racism.
A quick scan of Unwired doesn't reveal any clues.
I'd suggest that "trolling" would go out of vogue. Meta-hate aside, most slang terms don't tend to last sixty years, and the net is a rapidly-changing miasma of new cultural memes.
- "Booshwashing": Bumping gums; talking about nothing useful.
(It's fun, and sort of themey IMHO, to borrow historical "gangster-era" slang. I think somebody else on rpg.se suggested this to me on a different question. Ex: http://www.paper-dragon.com/1939/slang.html)
- "Milkfeed": Teen wannabe-netkiddie leeching off of their parents' MSP. Thinks they know it all. Someone who gets into arguments just to hear themself talk.
(It's always fun to make up your own, too.)
- "eThug": Nerd who thinks they're a bada** on the 'trix.
(My brother made this one up, referring to the modern internet.)
I would classify this as "Slotting/Slotting Off" to borrow from the phrase "Slot off, frag face!" from Shadowrun for the Sega Genesis/Mega Drive. This could be used as an accusation like
"Are you slotting (with) me?"
Griefing is an analogous term from computer gaming slang, I'm sure by whatever time Shadowrun is set, that word could have caught hold for forum abuse as well.
In the world of SR I would think that "Jacking" would be a good slur especially with the undertones and the reference to hijacking a thread, and pun on the datajacks.