Everyone knows, or should know by now, the cardinal rule of being a wedding guest.
Do not wear white on the big day, unless instructed to do so by the happy couple.
It's seen as an attempt to upstage the bride and steal focus from her and those who do it are often heavily criticised.
One woman recently shared photos from a wedding she attended and was branded "selfish" for committing the ultimate etiquette faux pas.
But, not only did she wear the colour, she also opted for a long, floaty dress that made her look like she was the one getting married.
The unnamed woman, who is engaged, posed in a white dress at the wedding with her fiance.
She shared the picture on social media and was forced to clarify that while she and her partner looked like a bride and groom in the shot - it was not her wedding.
The image did the rounds online and ultimately ended up on Reddit, where users were less than impressed by the whole thing.
The post was captioned: "The fact that the (engaged) woman in the photo captioned it 'not their wedding', shows she's self aware about wearing white to a wedding, but chose to do so anyway."
One person replied: "I think, if one of my friends is so disrespectful to put a white dress on my wedding I will ask her to leave or don’t appear in the pictures. Like what is the f***ing excuse to be so selfish to wear white dude."
Another said: "I think I'd be fine with white, but not when the dress actually looks like a wedding dress."
A third added: "I hope the bride goes to that friend's party using not just a white dress also but a white dress that really looks like a wedding one. That's what I would do in her shoes hahahah."
Someone else wrote: "I didn't read the caption and was just thinking how pretty the bride's dress was...damn."
