Posting to Twitter with big images

Hi, I need some help to understand what I did and why I cannot do it again, when I’m tweeting a post, please ??

About last week or so, I was surprised to see that my tweets appeared nicely with big images. Please see here: https://twitter.com/travelways28 my last photos embedded to twitter ( Kuna Vendors, Bocas del Toro Caribbean Art, If the doors could talk – Casco Viejo, Panama and Peggy’s Cove Lighthouse) Those photos appeared there in my gallery without me uploading them there manually. I just post them on my site (https://travelways.com/). I remember I had a plugin that automatically posted my posts to the social media. Since it was posting every time I was updating something, I didn’t want to keep it, so I delete it. Now I think that I better go and manually delete the duplicate posts in twitter and have them nicely displayed there, rather than having just text links to my posts…

Can you please illuminate me about what plugin was that and if there are maybe other similar ones?

Thanks in advance,

Tatiana