Keyboard worrier. 

Some one who caps locks you in an argument and thinks they are great for being able to. And also only makes fun of you on the internet and doesn't say it to your face.

Example: Stop caps locking me and thinking your the best... You little keyboard worrier.

Keyboard worrier. by sparkleyes10 May 16, 2013

Keyboard-worrier 

A paranoid tech savvy hypochondriac who posts toxic Ill informed rants online.

Look at this fake news doomsday shitpost.
Another bloody Keyboard-worrier!

Keyboard-worrier by Just the flu March 25, 2020