Shipping Label not completely printed

[nidsel]

I am having  an issue with shipping label printing.   

The big letter "F" (first class) or "P" (Priority) at the upper left corner of the label does not print.  it is left blank, but everything else is printed.   I am using Firefox. --how can I solve this issue? can anyone drop me some tips, please? I'd really appreciate your help.

Also, Can I still use the label even its not completely printed? Although the big letter "F" or "P" is missing, every thing else is printed. addresses, barcode...  are all there. 

(By the way, I have no issue with label printing if I switch to MS edge, but I prefer to use Firefox browser, so if anyone had the same issue before, please share your solutions. 

[nidsel]

if you are having the same problem as I am, here is the solution,

go to Firefox "settings" -->Application -->Content-->

How Firefox handles the file you download from web,

then choose "use Adobe Acrobat Reader"  instead of "open in Firefox"

[rfmtm]

Make sure your browser is set to open PDF files with Adobe and not its built in reader. 

Also this problem can happen if Orientation in the Adobe label preview window is not set to Auto, especially if you are using a thermal label printer. 

If still a problem come back with printer model, label size, and whether the label preview looks correct?