Disable Button Completely on Mobile Browser

Hello, I have successfully disable a button on MOBILE view using this code below:
if (wixWindow.formFactor === “Mobile” ){
$w( “#button4” ).hide();
$w( “#button4” ).disable();
}
Problem is when a user switch his mobile browser to DESKTOP SITE . See attached photo.


When a user tap that it will change to DESKTOP SITE view and my button will be shown.

The button called PREVIEW , when they click it, it allows the user to preview the PDF file before they can download it.
I only want my users to download the PDF file in the DOWNLOAD button I created because I am recording and tracking the download activity of our website.

On the desktop view (laptop or PC) , PREVIEW button is visible and the PDF VIEW TOOLBAR is disable, on the HTML frame i use “#toolbar=0” but on the mobile device it doesn’t have tool bar and preview function, but it has a Open button which the file will save to your mobile device. See second attached photo.

I just found out that some of the browsers wont recognize this code " # toolbar =0&statusbar=0&navpanes=0" :frowning:
So i guess i am giving up preview functionality or i will just have to make 3-4 PDF pages for preview functionality which is not so convenient. xD