the symbol refers to the historic actions of Jews which have caused their surnames to “echo throughout history”.

i had no idea that was the origin
the fuck does that even mean? there's a bunch of Cohens so "the Jews" rule the world?
god damn, the Smiths must be galactic overlords or some shit

neo-Nazi blog The Right Stuff

Let's look into that...

The Right Stuff is a neo-Nazi,^[1][2][3]^ antisemitic^[4]^ and white nationalist^[5]^ blog and discussion forum and the host of several podcasts, including The Daily Shoah. Founded by American neo-Nazi Mike Enoch, the website promotes Holocaust denial,^[6]^ and coined the use of "echoes", an antisemitic marker that uses triple parentheses around names to identify Jewish people.

Doxing incident

In early 2017, Mike Enoch was doxed by fellow neo-Nazis, who revealed that his real name was Mike Peinovich. They also released biographical information which they believe contradicts his professed ideology.^[20][21]^ The dox revealed that Enoch's wife was Jewish and that their wedding had featured traditional Jewish rites and chanting. Enoch was mocked by other neo-Nazis for his Serbian surname; historically, Nazi Germany had classified Serbs as a subhuman race and the Croatian Ustaše puppet regime had perpetrated a genocide of Serbs.

After the doxing, some of Enoch's followers reacted angrily to the information that had been revealed. They circulated forged images of him and his wife which derided their ethnicities.^[1]^ Salon journalist Matthew Sheffield posited that Neo-Nazi podcast listeners speculated that Enoch was Jewish, "controlled opposition", or otherwise disingenuous in his beliefs.

What a thing.

The neo-Nazi triple parentheses, forresten, are not to be confused with the Runet equivalent to LOL, which is just putting three end parentheses at the end of your sentence like so))) — I've also seen open parentheses to indicate feeling sad, like so(((

It's also noted that (((triple parentheses))) were historically texting slang for a "cyberhug", but nobody does that anymore for obvious reasons.

Neo-Nazis also use )))inverted triple parentheses((( around the names of antisemites, and some Jews use triple parentheses around their own names as a form of reclamation.

There was also a podcast or some shit that would make mentions of Jews echo, which AFAIK was where the dogwhistle started. So if they were talking about a Jewish person named "Rothstein," the name would sound like "R-rothstein...stein...stein..." while the rest of their sentence was unaltered. Transcripts of the podcast would use parentheses to demonstrate the effect.