When importing a PDF I get an unexpected popup

[Images on Paper]

Just started this morning, I drag and drop a PDF onto Illustrator to open it and I get this popup. I use Extensis Connect Fonts (previously Suitcase Fusion) on this PC. Any ideas how to stop this happening?

[Ton Frederiks]

Does it open normally when using File > Open?

Do you have the most recent Extensis version?

Did you check Extensis support?