What's a time a man mansplained to you?

Programmers, with whom I'd worked with my early career (about a dozen years) are particularly prone to mansplaining. The worst case was a candidate for a "no assholes rule" dismissal who in the course of one company pizza lunch:
Told me what marketing "really" was. (I have a degree in it. He doesn't.)
Gave me repeated unsolicited advice on how to market the company's products.
Told me that my marketing campaign for one product (his) was garbage and that I should talk to the person who did the marketing for another product to learn how to "do it right". I did the marketing for that other product too....
Also told me how much make-up I should use and how to apply it because apparently he's an expert on feminine health and beauty.
I mentioned the "no assholes rule" I think? He was later canned for being an asshole, despite his apparently very formidable technical skills.
- I swear the higher incidence of neurodivergence among programmers has something to do with the increased likelihood of their mansplaining, something about the pedantic, socially-unaware, info-dumping often comes across that way 🫠
  
  I think there's some of that. These would be the "geek" styles, though. Not the brodude types.
  I like the geek programmers. (I can read past the awkwardness.) Brodude types, though, make my skin crawl.
  
  There's some of that, but there is also a huge chunk of egotism and misogyny.
  Source: ASD tech married to an ADHD dev.
- Hahahha reminds of a particular work arsehole who tried to lecture me on a technical task and told me to read a piece of documentation he found on the company intranet. I told him to look up who authored the fucking thing (me)
  
  That happens so often it's scary. "Well, according to Rutland and co. you..." "I'm the Rutland in 'Rutland and co...'"

A man who knew my specialist area was domestic abuse started Informing Me about how more men are abused by women than vice versa and they just didn't report because they were ashamed. Unsurprisingly BTW, the man telling me this was a domestic abuse perp. I politely poured water on his theory using evidence and he glowered.
Around 18 years ago a man patronisingly informed me about what Wikipedia was. It was well known by that time! But obviously, being a mere woman, I wouldn't know. He was a bit weird as well, quite creepy with a few women
- Ugh. The people who think I don't know about web sites or technologies because I don't use them really tick me off.

I was a bit into my transition when a colleague started explaining the basics of VHDL to me after I had pointed out to him that the bug in his design had all the hallmarks of an off-by-one. (Thanks, buddy, I have a postgraduate degree in this). I was so baffled because that sort of stuff had never happened to me before.
Then he was going over the code and explaining how there is no off-by-one when I pointed out that his integer type was indeed one bit smaller than it needed to be.
He of course tried to take credit for fixing that bug, but guess which girl was the one with merge permissions in gitlab.
I’ve also had several men try to explain to me how the vending machine in the office works, even as I was using it. That one gives me a laugh every time.
- How nice of them to affirm your gender like that 😂 they were just being supportive!

Yesterday, at my job as a reporter. Some men, even though I tell them how the interview/quoting process works, will just assume I'm stupid for asking "groundwork" questions without realizing I'm doing that to get quotes, which I need in his words, not mine.
I should also say my job is borderline public relations work, so I wasn't asking probing, hardball gotcha questions either. The articles are essentially free advertising for companies.
Sometimes, they'll get that I understand what I'm asking about as the interview progresses, but this man continued to give me condescending, non-sentence answers while repeatedly questioning my knowledge on the subject. Which will just make it harder to grab good quotes when I write the article, because they all come with spice. I never have these problems when I interview women.
- Oh good grief. There was no need to be condescending, if he thought you were being ridiculous he could have just asked you why you were asking these questions. But instead he chose to rub your face in his superiority and try to embarrass you in the process. Did he realise he faceplanted?

I'm often told how to can by guys who watched their grandmothers can and who have no idea what the Ball Blue Book even is. Like, just cause your memaw had horrific canning practices and survived doesn't make it safe. Or smart. Or anything other than lucky.
Also yes. I do know what purling is, guy watching me knit. Who said it so condescendingly I thought I was going insane until another guy actually asked him wtf and he just...left???

“Deleted” my comment because I was told this community is women and Trans exclusive.
- Thanks for deleting Sit it's really kind of you
- Hey sit thanks so much for your comment! We are a trans+ inclusive women's community so please don't comment again 😊

I have a trainee in my team, he's reasonably good at his job, but he has a habit of explaining things to me that I explained to him in the last month.
Still, better than the guy who I had to show even basic tasks 3 times. Who when he didn't do it right, and didn't ask for help, blamed me ... despite his signature being on the records.
- Oh ffs. Blame shifting is a classic abusive personality characteristic, and at best it shows he's a dick.
  
  Indeed, he filed complaints for abusive behaviour against me, my boss (also a woman) and the only POC on the team, got the union to support him, and was then signed off sick for stress for 6 months ... he was fired in the end, and the union reps (all dudes) apologised for just taking him at his word.
  TBH I'm just glad he's gone, morale has shot through the roof and we're crushing it now :-)

Not my own story, but a friend of mine (who is also trans) got lectured by a guy 30yrs older than her about how hrt is bad for you after they'd fucked. That was a wild story to hear.
I kinda don't tend to hang out with cis men enough to experience mansplaining myself; though I have a vague memory that someone who was clearly clueless about how VRC works tried to correct me on someone avatar related and refused to accept they were wrong.

I had a younger male coworker a few years back who explained to me what a progress bar in a computer program is.

I was doing physical therapy for back pain, and the therapist noted that I had pelvic floor disfunction. I needed to get approval from an obgyn for them to do an internal exam. I was new in town, so this was my first visit to the obgyn.
I'm there in a paper gown, sitting on the edge of one of those stupid beds, while doctor goes on an endless lecture about how the uterus works, most of which I already know, none of which is relevant to my visit. I interrupted: "I'm going to stop you there. Are we going to be doing an exam, or can we finish this conversation elsewhere, because my back hurts."
He looks surprised. "Oh. Maybe you do have back pain."
Thankfully, my most recent visit with him went well, and his explanations were relevant and welcome.