The preview icon

[ajtruckle]

Is it possible to make the on / off state of the preview button more prominent?

[toopay]

Like....

[ajtruckle]

How about just like it is done in Git hub?

Or, a toggle from "Preview" to "Write". It is just that I am colour blind and I don't really see any difference with that button when it is "on" or "off".

[BudgieInWA]

Like #132.