I decided to install firefox nightly on my windows 10 pro / 64-bit edition laptop early this morning because I already have it installed on two different computers with the exact same operating system installed. On those computers when I pin a desired site they remain there until I decide to manually unpin them. That's not the case with my installation here on my laptop, after having pinned a site the proper way & then going to a different site and upon returning to the original new tab page where I had previously pinned a desired site it no longer appears...why ? Thanks, David