The Editor and Reader Mode Icon is flipped around. It is confusing to the eyes, unless I choose to remember it or make it as a habit, it’s hard to distinguished based on icon.
The Reader Icon should be displayed when on Reader Mode and the Editor Icon should be displayed when on Editor Mode. For example, When Something is On, it should be displayed as ON, and when something is Off it should be displayed as OFF. Another example is Online and Offline, when a User is Online, it should be displayed as Online, and when a user is offline, the mode should display offline.
Usually, I just Type to see if I am on editor mode. If it fails to display text, then I know I am on reader mode, if it displays text, I know I am on editor mode.