eww, worst combination ever, I am an NVDA user, but on my work laptop I am forced to use whatever they have installed, and needless to say it's a secured environment so can't add anything with it. Anyway long story short I have the exact combination, jaws 2018 and Edge, and it's buggy as hell, heck I sometimes use internet explorer to avoid this problem.
Don't use Edge with Jaws 2018, never
Indeed Jaws does not read the text you type in the text boxes, but it gets written. Also it does strange jumps on me when activating some buttons or some links, just goes to the desktop or taskbar, whatever it feels like, And just a bunch of other weird things.
“If you live each day as if it was your last, someday you’ll most certainly be right.”