If you cannot see any content on pages you printed or in print preview, the cause might be margins which are set too high.

1. In order to check the margins, we need to go to File > Page Setup.
2. Once this is done, switch to the Margins & Header/Footer tab.
3. Check what's set there under Margins.

The following are the default values for Margins:

Right: 12.7

Top: 12.7

Left: 12.7

Bottom: 12.7

Check these values accordingly and change them if necessary.

Is there any obvious visual difference between barcodes or other fonts printed in Firefox 19 and Firefox 20? For example, "boldness" for lack of a better word. I ask because we had a Windows 7 user whose Arial all turned into Arial bold. If you wouldn't mind, could you review the suggestions in that thread: why all fonts in all sites same size even unread and read text ?

one solution of this i see in 19 version and 20 print font different so i change my bar-code font size increase so my problem solve .

Why not try to use a different barcode generator or barcode reader?