Print Toolbar Icon Differences and Descriptions

[Panch]

I have a question about two print toolbar icons, described as follows:
(1) Just the printer icon itself, (2) the printer icon with three dots beneath it.
So far no luck finding answers in the manual. On page 646 of thee manual, I do not see a listing of number one above. There are only the printer icon with three dots and the print preview icon. Why is this?
When I click on icon number one in the above list, the pop-up description is "Print document with default settings".
If "default settings" refers to my printer settings or to the settings in the Textmaker print window, both sets of those settings are for two-sided printing, as I have set them up, making two-sided printing the default, best I can tell.
But if I click on the number one icon in my Textmaker toolbar, the output is single sheet printing, which is not the printing default I have set.
If I click on the second icon type with three dots, I get two-sided printing, which is the default I have set.
So why is the first icon, the image of a printer by itself, described in a Texmaker pop-up as "print document with default settings", when it is the second icon with three dots that actually prints the printing defaults I have set? And how is it that I can have a printer icon with no dots in the toolbar, but this icon is not in the manual icon list?
Can someone clear this up for me?