Btw big tip about how to get better at noticing dogwhistles (defined and explained: x, x, x, x, x, x, x) and making sure you don't accidentally reblog or spread them, from a professional editor specializing in sensitivity and an erstwhile professional fact-checker:
A lot of dogwhistles hinge on very specific phrasing and/or typography.
Because we also use very specific phrasing and/or typography as a way to convey things like tone, sarcasm, and memes over text, a lot of people see something in a post that makes them lowkey go "huh? what's that about?" But this happens all the time with online linguistics and communication so people just brush it off for various reasons.
So if you see something that pings you as unusual, idiosyncratic, or overly specific, and you're not sure why, make it a principle to not reblog (or repost, on other sites, etc.) any posts where you're like "Hmm. I think this post might be doing a Communication Thing but I'm not sure what it means."
Examples/specific things to be careful of:
Alternate spellings. For example, variant spellings of women/woman are often a TERF dogwhistle, such as womyn and more rarely wombyn (x, x, x, x). (In contrast, though, womxn was specifically intended to be trans/nonbinary inclusive, although it gets a mixed reception in practice (x, x))
Portmanteaus and suffixes (that you don't know the specific meaning of). A lot of acronyms are textspeak, but a lot of them aren't. Examples include "sheeple" and any words that seem to be derived from sheeple, which is very broadly associated with conspiracy theories, especially in far right and anti-government movements (x, x, x). Be especially cautious of anything that's a compound with the suffix -gate or the word pill/pilled. These both have legitimate uses: For -gate, it's used in mainstream politics and jargon to signify a conspiracy or scandal, named after Watergate (x, x), but since it specifically refers to conspiracies, it is often used in far-right conspiracies, such as pizzagate, a conspiracy theory that resulted in a targeted mass shooting (x, x, x). For "pill"/"pilled," the term refers to radicalizing as an MRA/Men's Rights Activist and is now associated with far-right radicalization across the board - it is used both by members of those groups, and critically by outsiders to refer to the process of such radicalization (x, x, x, x, x).
Anything that compares people to animals, or overly associates them with animals, especially BIPOC. Examples of specific dogwhistles include associating Black people in particular and now Latinx people with alligators or depicting BIPOC as being eating by alligators (x, x, x, x, x), and associating Jewish people with lizards and reptiles, especially references to "lizard people" (x, x, x, x, x)
Any unusual numbers or typography that you don't know the specific meaning of. Examples of this include the Nazi and antisemitic dogwhistles of 14, 88, and 1488 (x, x, x), as well as using three sets of parentheses around the name of a person (((Like This))) or profession, e.g. (((banker))) to indicate that they're Jewish/assumed to be Jewish and deliberately indicate belief in giant antisemitic conspiracy theories (x, x, x) (though this one has been somewhat reclaimed by Jewish people (x), so evaluate context)
Terms that sound like they might be academic (but you're not familiar with a specific academic meaning). A lot of bigotry is deeply rooted in and reinforced by the history of science, particularly in the context of biology, pseudoscience, and scientific racism. And also, a lot of bigots like to dress their prejudice and hate up in fancy bullshit pseudoscience and pseudo-academic theories. (And just in case I need to mention it: the prefix pseudo- very specifically means false, not "unproven" or "eh something we're kind of vague on.") Examples of transphobic dogwhistles that sound like academic theories (or are absolute bullshit "academic" theories) include "gender critical [ideology]," "[male/female] socialization," and "rapid-onset gender dysphoria" (x, x, x, x).
tl;dr: If you see something in a post, esp. typography or phrasing, that pings you as unusual, idiosyncratic, or overly specific, and you're not sure why, don't share it without doing some research.