Don't work for me.
What I do to have a thumbnails with Instagram :

• In rules.json I delete the Instagram part.
• on Instagram I go to the page where the image is.
• I find the url source of the image in the code source
• I share this url source in shaarli and it works

On Shaarli, after replace web-thumbnailer by the last one.
I try on :

• an instagram profil page (ex: https://www.instagram.com/melfindash/ )
• an instagram image page (ex: https://www.instagram.com/p/CLobRofBfN2/ )
• the source images (ex: https://scontent-cdg2-1.cdninstagram.com/v/t51.2885-15/e35/s1080x1080/152045113_434431194280720_5656323718043532716_n.jpg?_nc_ht=scontent-cdg2-1.cdninstagram.com&_nc_cat=104&_nc_ohc=KWZooajXWOwAX8xYKFk&tp=1&oh=b5d71d699502e4cdd8d3efee45f5f951&oe=605F7A5B )

It won't make a thumbnail. But doing what I explain in the previous message work.
May be it's not the better way to test.

Sorry for the late reply. I just tried and it's working for me with the picture page. Note that I had to clear my thumbnails cache. However the profile one doesn't because Instagram redirects to the login page.

Let me update the dependency in Shaarli and try with a the real release.

It actually doesn't work on my production environment because Instagram redirects me to the login page even for picture pages. I need to investigate further to see if it's related to my IP, or if there are some headers that could be injected to avoid that.

Hi!
Maybe try ?

https://www.instagram.com/p/ --- ID --- /media/?size=l
https://www.instagram.com/p/CLobRofBfN2/media/?size=l