Firefox "print" prints some text on top of other text. How can I fix it?

Question

I want to print a webpage with a travel itinerary on it. The itinerary is quite long, exceeds the page height and overflows onto the next page. Unfortunately the information below the itinerary is then printed on top of the itinerary information on the overflow page.
I have tried the same page in Chrome, Safari and IE 10 and it prints correctly in all of them.
I use a css (print.css media='print') to control some of the print output.
Can anyone help please?
Application Basics
Name: Firefox
Version: 24.0
User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:24.0) Gecko/20100101 Firefox/24.0
Extensions
Name: DownloadHelper
Version: 4.9.14
Enabled: true
ID: {b9db16a4-6edc-47ec-a1f4-b86292ed211d}
Name: easy Xdebug
Version: 1.5
Enabled: true
ID: [email protected]
Name: Firebug
Version: 1.11.2
Enabled: true
ID: [email protected]
Name: Live HTTP headers
Version: 0.17
Enabled: true
ID: {8f8fe09b-0bd3-4470-bc1b-8cad42b8203a}
Name: Page Speed
Version: 1.12.9
Enabled: true
ID: {e3f6c2cc-d8db-498c-af6c-499fb211db97}
Name: DivX Plus Web Player HTML5 <video>
Version: 2.1.2.145
Enabled: false
ID: {23fcfd51-4958-4f00-80a3-ae97e717ed8b}
Name: FreeHDSport.TV
Version: 1.2
Enabled: false
ID: [email protected]
Name: Translate This!
Version: 2.0
Enabled: false
ID: jid0-k75TfRGfOXPHfEZmJ9cKu5eCgLc@jetpack
Important Modified Preferences
accessibility.typeaheadfind: true
accessibility.typeaheadfind.flashBar: 0
browser.cache.disk.capacity: 358400
browser.cache.disk.smart_size_cached_value: 358400
browser.cache.disk.smart_size.first_run: false
browser.cache.disk.smart_size.use_old_max: false
browser.places.smartBookmarksVersion: 4
browser.startup.homepage_override.buildID: 20130910160258
browser.startup.homepage_override.mstone: 24.0
dom.mozApps.used: true
dom.w3c_touch_events.expose: false
extensions.lastAppVersion: 24.0
gfx.blacklist.webgl.msaa: 4
network.cookie.prefsMigrated: true
places.database.lastMaintenance: 1382955114
places.history.expiration.transient_current_max_pages: 104858
plugin.disable_full_page_plugin_for_types: application/pdf
plugin.importedState: true
plugin.state.ovshelper: 0
print.macosx.pagesetup-2: PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4KPCFET0NUWVBFIHBsaXN0IFBVQkxJQyAiLS8vQXBwbGUvL0RURCBQTElTVCAxLjAvL0VO
print.print_bgcolor: false
print.print_bgimages: false
print.print_colorspace:
print.print_command:
print.print_downloadfonts: false
print.print_duplex: 0
print.print_evenpages: true
print.print_in_color: true
print.print_margin_bottom: 0.5
print.print_margin_left: 0.5
print.print_margin_right: 0.5
print.print_margin_top: 0.5
print.print_oddpages: true
print.print_orientation: 0
print.print_page_delay: 50
print.print_paper_data: 0
print.print_paper_height: 11.00
print.print_paper_name:
print.print_paper_size_type: 1
print.print_paper_size_unit: 0
print.print_paper_width: 8.50
print.print_plex_name:
print.print_resolution: 0
print.print_resolution_name:
print.print_reversed: false
print.print_scaling: 1.00
print.print_shrink_to_fit: true
print.print_to_file: false
print.print_unwriteable_margin_bottom: 57
print.print_unwriteable_margin_left: 25
print.print_unwriteable_margin_right: 25
print.print_unwriteable_margin_top: 25
privacy.cpd.offlineApps: true
privacy.cpd.siteSettings: true
privacy.donottrackheader.enabled: true
privacy.sanitize.migrateFx3Prefs: true
privacy.sanitize.timeSpan: 0
security.csp.enable: false
security.OCSP.enabled: 0
security.warn_viewing_mixed: false
storage.vacuum.last.index: 1
storage.vacuum.last.places.sqlite: 1381489144
user.js Preferences
Your profile folder contains a user.js file, which includes preferences that were not created by Firefox.
Graphics
Device ID: 0x fd5
GPU Accelerated Windows: 1/1 OpenGL
Vendor ID: 0x10de
WebGL Renderer: NVIDIA Corporation -- NVIDIA GeForce GT 650M OpenGL Engine
windowLayerManagerRemote: false
AzureCanvasBackend: quartz
AzureContentBackend: none
AzureFallbackCanvasBackend: none
JavaScript
Incremental GC: true
Accessibility
Activated: false
Prevent Accessibility: 0
Library Versions
NSPR
Expected minimum version: 4.10
Version in use: 4.10
NSS
Expected minimum version: 3.15.1 Basic ECC
Version in use: 3.15.1 Basic ECC
NSSSMIME
Expected minimum version: 3.15.1 Basic ECC
Version in use: 3.15.1 Basic ECC
NSSSSL
Expected minimum version: 3.15.1 Basic ECC
Version in use: 3.15.1 Basic ECC
NSSUTIL
Expected minimum version: 3.15.1
Version in use: 3.15.1

Answer 1

Hi midnig-
I found this article on troubleshooting print issues:
http://mzl.la/MCCq7H
I see that you have covered some of the basic troubleshooting tips- but you might try resetting the printer. Here are some other suggestions:
- If you have made changes to Advanced font settings like increasing the minimum/default font size then try the default minimum setting "none" and the default font size 16 in case the current setting is causing problems.
- Tools > Options > Content : Fonts & Colors > Advanced > Minimum Font Size (none)
Make sure that you allow pages to choose their own fonts.
- Tools > Options > Content : Fonts & Colors > Advanced: [X] "Allow pages to choose their own fonts, instead of my selections above"
It is better not to increase the minimum font size, but to use an extension to set the default page zoom to prevent issues with text not being displayed properly.
- You can use an extension to set a default font size and page zoom on web pages.
Default FullZoom Level: https://addons.mozilla.org/firefox/addon/default-fullzoom-level/
NoSquint: https://addons.mozilla.org/firefox/addon/nosquint/