Embedded pdf in firefox quantum


I have just swotched to FF quantum.
Is much more light and quick.
But I have noticed that pdf does not get opened embeded, istead they are downloaded.
I was using embeded okular to display pdf’s.
Is there a way to configure it?
Using plasma 5.8.7


firefox 57 blocks all plugins except for flash, pdf’s should be handled internally by pdf.js
I’m guessing you disabled pdf.js so Okular would work, quantum does not support plugins anymore this is by design
if you want pdf’s to be handled in the browser not downloaded pdf.js is your only choice
in the address bar type about:config
and see the value of the Boolean pdfjs.disabled it should be false if it’s not toggle it as is should default to false

I had it enabled but i have just found that in preferences-applications “portable PDF document” whas set to “save” instead to preview in firefox.