Might I also add that I assemble my own system and run Hackintosh on it 
I looks like FoxReader is one of those pesky app to remove from Linux s
ystem. I wonder if @Aravisian have some idea how to remove it from your system.
[edit]
I think I found it. Instruction for Ubuntu 20.04 (which Zorin 16 is based on)



from the mod.

