For the second time in the past several weeks I've had a popup appear on my screen. This popup takes up the entire screen and asks me to install some software. The first time, I accidentally closed it before I could read it or understand what it was. The second time, just now, I was able to screenshot it.

"presage" does anyone know what this is? It happened to open today when I opened Instagram, but I don't know if it's related.

I tried to search and found nothing.

Screenshot linked below.

https://www.dropbox.com/s/tg08occrjukmkrj/Screenshot_2014-10-29-14-33-01.png?dl=0