Compilation under Windows: go build -ldflags -H=windowsgui

You can change the icon by creating your own and then run:

fyne bundle icon.png > icon.go

Please note: I used in the code at line 29 the same parameters
as described in Go's crypto package description, for Argon2id:

https://godoc.org/golang.org/x/crypto/argon2

Please finetune the parameters to your machine specs and your
requirements.