Print jobs with shadowed text

Hi,

I'm having some dificulty, finding which options to change so my print jobs won't come out shadowed, like they were printed in 3D!

If i print just plain text in VIM or Kate, it comes out fine.
But if i use Okular or Firefox to print pdf files, text and images on those files are printed with shadows like some 3D efect!
There are cases where if a header and a footer exists, it's printed out correctly! Colored or black. Everything else is shadowed!

One example: If i print my CV in OpenOffice (odt file) or in Okular (pdf file), the headers and footers (in light blue) come out fine, but the main content of the pages (dark blue and black text) come out shadowed!

Another example: If i print this form in firefox (just the first page where the similar questions found are presented in blue hyperlinks), the linux logo image, the log out button, the language button, the summary text box content and the blue hyperlinks are printed shadowed! All the rest throughout the page is printed correctly!

Please help!

My system: Slackware 14.2
My printer: HP Photosmart C4780
My hp-check log content:
hp-check[12795]: info: :
hp-check[12795]: info: :HP Linux Imaging and Printing System (ver. 3.17.11)
hp-check[12795]: info: :Dependency/Version Check Utility ver. 15.1
hp-check[12795]: info: :
hp-check[12795]: info: :Copyright (c) 2001-15 HP Development Company, LP
hp-check[12795]: info: :This software comes with ABSOLUTELY NO WARRANTY.
hp-check[12795]: info: :This is free software, and you are welcome to distribute it
hp-check[12795]: info: :under certain conditions. See COPYING file for more details.
hp-check[12795]: info: :
hp-check[12795]: info: :Note: hp-check can be run in three modes:
hp-check[12795]: info: :1. Compile-time check mode (-c or --compile): Use this mode before compiling the HPLIP supplied
hp-check[12795]: info: :tarball (.tar.gz or .run) to determine if the proper dependencies are installed to successfully
hp-check[12795]: info: :compile HPLIP.
hp-check[12795]: info: :2. Run-time check mode (-r or --run): Use this mode to determine if a distro supplied package (.deb,
hp-check[12795]: info: :.rpm, etc) or an already built HPLIP supplied tarball has the proper dependencies installed to
hp-check[12795]: info: :successfully run.
hp-check[12795]: info: :3. Both compile- and run-time check mode (-b or --both) (Default): This mode will check both of the
hp-check[12795]: info: :above cases (both compile- and run-time dependencies).
hp-check[12795]: info: :
hp-check[12795]: info: :Check types:
hp-check[12795]: info: :a. EXTERNALDEP - External Dependencies
hp-check[12795]: info: :b. GENERALDEP - General Dependencies (required both at compile and run time)
hp-check[12795]: info: :c. COMPILEDEP - Compile time Dependencies
hp-check[12795]: info: :d. [All are run-time checks]
hp-check[12795]: info: :PYEXT SCANCONF QUEUES PERMISSION
hp-check[12795]: info: :
hp-check[12795]: info: :Status Types:
hp-check[12795]: info: : OK
hp-check[12795]: info: : MISSING - Missing Dependency or Permission or Plug-in
hp-check[12795]: info: : INCOMPAT - Incompatible dependency-version or Plugin-version
hp-check[12795]: info: :
warning: 8-14.2 version is not supported. Using 8-12.1 versions dependencies to verify and install...
hp-check[12795]: info: :
hp-check[12795]: info: :---------------
hp-check[12795]: info: :| SYSTEM INFO |
hp-check[12795]: info: :---------------
hp-check[12795]: info: :
hp-check[12795]: info: : Kernel: 4.4.14-v2 #4 SMP PREEMPT Sat Apr 1 23:28:50 WEST 2017 GNU/Linux
 Host: graundechefe
 Proc: 4.4.14-v2 #4 SMP PREEMPT Sat Apr 1 23:28:50 WEST 2017 GNU/Linux
 Distribution: 8 14.2
hp-check[12795]: info: : Bitness: 64 bit

hp-check[12795]: info: :
hp-check[12795]: info: :-----------------------
hp-check[12795]: info: :| HPLIP CONFIGURATION |
hp-check[12795]: info: :-----------------------
hp-check[12795]: info: :
hp-check[12795]: info: :HPLIP-Version: HPLIP 3.17.11
hp-check[12795]: info: :HPLIP-Home: /usr/share/hplip
warning: HPLIP-Installation: Auto installation is not supported for 8 distro 14.2 version
hp-check[12795]: info: :
hp-check[12795]: info: :Current contents of '/etc/hp/hplip.conf' file:
hp-check[12795]: info: :# hplip.conf. Generated from hplip.conf.in by configure.

[hplip]
version=3.17.11

[dirs]
home=/usr/share/hplip
run=/var/run
ppd=/usr/share/ppd/HP
ppdbase=/usr/share/ppd
doc=/usr/doc/hplip-3.17.11
html=/usr/doc/hplip-3.17.11/html
icon=/usr/share/applications
cupsbackend=/usr/lib64/cups/backend
cupsfilter=/usr/lib64/cups/filter
drv=/usr/share/cups/drv/HP
bin=/usr/bin
apparmor=/etc/apparmor.d
# Following values are determined at configure time and cannot be changed.
[configure]
network-build=yes
libusb01-build=no
pp-build=yes
gui-build=yes
scanner-build=yes
fax-build=yes
dbus-build=yes
cups11-build=no
doc-build=yes
shadow-build=yes
hpijs-install=yes
foomatic-drv-install=yes
foomatic-ppd-install=no
foomatic-rip-hplip-install=yes
hpcups-install=yes
cups-drv-install=yes
cups-ppd-install=yes
internal-tag=3.17.11
restricted-build=no
ui-toolkit=qt4
qt3=no
qt4=yes
qt5=no
policy-kit=yes
lite-build=no
udev_sysfs_rules=no
hpcups-only-build=no
hpijs-only-build=no
apparmor_build=no
class-driver=no

hp-check[12795]: info: :
hp-check[12795]: info: :Current contents of '/var/lib/hp/hplip.state' file:
hp-check[12795]: info: :Plugins are not installed. Could not access file: No such file or directory
hp-check[12795]: info: :
hp-check[12795]: info: :Current contents of '~/.hplip/hplip.conf' file:
hp-check[12795]: info: :[installation]
date_time = 04/07/18 11:20:48
version = 3.17.11

[settings]
systray_visible = 0
systray_messages = 0

[last_used]
device_uri = "hp:/net/Photosmart_C4700_series?ip=192.168.0.71"
printer_name = Photosmart_C4700
working_dir = .

[commands]
scan = /usr/bin/xsane -V %SANE_URI%

[refresh]
rate = 30
enable = false
type = 1

[polling]
enable = false
interval = 5
device_list =

[fax]
voice_phone =
email_address =

[upgrade]
notify_upgrade = true
last_upgraded_time = 1518967279
pending_upgrade_time = 0

hp-check[12795]: info: : <Package-name> <Package-Desc> <Required/Optional> <Min-Version> <Installed-Version> <Status> <Comment>
hp-check[12795]: info: :
hp-check[12795]: info: :-------------------------
hp-check[12795]: info: :| External Dependencies |
hp-check[12795]: info: :-------------------------
hp-check[12795]: info: :
hp-check[12795]: info: : cups CUPS - Common Unix Printing System REQUIRED 1.1 2.1.4 OK 'CUPS Scheduler is running'
hp-check[12795]: info: : gs GhostScript - PostScript and PDF language interpreter and previewer REQUIRED 7.05 9.19 OK -
hp-check[12795]: info: : xsane xsane - Graphical scanner frontend for SANE OPTIONAL 0.9 0.999 OK -
hp-check[12795]: info: : scanimage scanimage - Shell scanning program OPTIONAL 1.0 1.0.25 OK -
hp-check[12795]: info: : dbus DBus - Message bus system REQUIRED - 1.10.8 OK -
hp-check[12795]: info: : policykit PolicyKit - Administrative policy framework OPTIONAL - 0.113 OK -
hp-check[12795]: info: : network network -wget OPTIONAL - 1.18 OK -
hp-check[12795]: info: : avahi-utils avahi-utils OPTIONAL - 0.6.32 OK -
hp-check[12795]: info: :
hp-check[12795]: info: :------------------------
hp-check[12795]: info: :| General Dependencies |
hp-check[12795]: info: :------------------------
hp-check[12795]: info: :
hp-check[12795]: info: : libjpeg libjpeg - JPEG library REQUIRED - - OK -
hp-check[12795]: info: : cups-devel CUPS devel- Common Unix Printing System development files REQUIRED - 2.1.4 OK -
hp-check[12795]: info: : cups-image CUPS image - CUPS image development files REQUIRED - 2.1.4 OK -
hp-check[12795]: info: : libpthread libpthread - POSIX threads library REQUIRED - b'2.23' OK -
hp-check[12795]: info: : libusb libusb - USB library REQUIRED - 1.0 OK -
hp-check[12795]: info: : sane SANE - Scanning library REQUIRED - 1.0.25 OK -
hp-check[12795]: info: : sane-devel SANE - Scanning library development files REQUIRED - 1.0.25 OK -
hp-check[12795]: info: : libnetsnmp-devel libnetsnmp-devel - SNMP networking library development files REQUIRED 5.0.9 5.7.3 OK -
hp-check[12795]: info: : libcrypto libcrypto - OpenSSL cryptographic library REQUIRED - 1.0.2 OK -
hp-check[12795]: info: : python3X Python 2.2 or greater - Python programming language REQUIRED 2.2 3.6.4 OK -
hp-check[12795]: info: : python3-notify2 Python libnotify - Python bindings for the libnotify Desktop notifications OPTIONAL - - OK -
hp-check[12795]: info: : python3-pyqt4-dbus PyQt 4 DBus - DBus Support for PyQt4 OPTIONAL 4.0 4.12.1 OK -
hp-check[12795]: info: : python3-pyqt4 PyQt 4- Qt interface for Python (for Qt version 4.x) REQUIRED 4.0 4.12.1 OK -
hp-check[12795]: info: : python3-dbus Python DBus - Python bindings for DBus REQUIRED 0.80.0 1.2.4 OK -
hp-check[12795]: info: : python3-xml Python XML libraries REQUIRED - 2.1.0 OK -
hp-check[12795]: info: : python3-devel Python devel - Python development files REQUIRED 2.2 3.6.4 OK -
hp-check[12795]: info: : python3-pil PIL - Python Imaging Library (required for commandline scanning with hp-scan) OPTIONAL - 1.1.7 OK -
hp-check[12795]: info: : python3-reportlab Reportlab - PDF library for Python OPTIONAL 2.0 3.4.0 OK -
hp-check[12795]: info: :
hp-check[12795]: info: :--------------
hp-check[12795]: info: :| COMPILEDEP |
hp-check[12795]: info: :--------------
hp-check[12795]: info: :
hp-check[12795]: info: : libtool libtool - Library building support services REQUIRED - 2.4.6 OK -
hp-check[12795]: info: : gcc gcc - GNU Project C and C++ Compiler REQUIRED - 5.3.0 OK -
hp-check[12795]: info: : make make - GNU make utility to maintain groups of programs REQUIRED 3.0 4.1 OK -
hp-check[12795]: info: :
hp-check[12795]: info: :---------------------
hp-check[12795]: info: :| Python Extentions |
hp-check[12795]: info: :---------------------
hp-check[12795]: info: :
hp-check[12795]: info: : cupsext CUPS-Extension REQUIRED - 3.17.11 OK -
hp-check[12795]: info: : hpmudext IO-Extension REQUIRED - 3.17.11 OK -
hp-check[12795]: info: :
hp-check[12795]: info: :----------------------
hp-check[12795]: info: :| Scan Configuration |
hp-check[12795]: info: :----------------------
hp-check[12795]: info: :
hp-check[12795]: info: : hpaio HPLIP-SANE-Backend REQUIRED - 3.17.11 OK 'hpaio found in /etc/sane.d/dll.conf'
hp-check[12795]: info: : scanext Scan-SANE-Extension REQUIRED - 3.17.11 OK -
hp-check[12795]: info: :
hp-check[12795]: info: :------------------------------
hp-check[12795]: info: :| DISCOVERED SCANNER DEVICES |
hp-check[12795]: info: :------------------------------
hp-check[12795]: info: :
hp-check[12795]: info: :device `hpaio:/net/Photosmart_C4700_series?ip=192.168.0.71' is a Hewlett-Packard Photosmart_C4700_series all-in-one
device `v4l:/dev/video0' is a Noname USB2.0 Camera virtual device

hp-check[12795]: info: :
hp-check[12795]: info: :--------------------------
hp-check[12795]: info: :| DISCOVERED USB DEVICES |
hp-check[12795]: info: :--------------------------
hp-check[12795]: info: :
hp-check[12795]: info: :No devices found.
hp-check[12795]: info: :
hp-check[12795]: info: :---------------------------------
hp-check[12795]: info: :| INSTALLED CUPS PRINTER QUEUES |
hp-check[12795]: info: :---------------------------------
hp-check[12795]: info: :
hp-check[12795]: info: :
hp-check[12795]: info: :Photosmart_C4700
hp-check[12795]: info: :----------------
hp-check[12795]: info: :Type: Printer
hp-check[12795]: info: :Device URI: hp:/net/Photosmart_C4700_series?ip=192.168.0.71
hp-check[12795]: info: :PPD: /etc/cups/ppd/Photosmart_C4700.ppd
hp-check[12795]: info: :PPD Description: HP Photosmart c4700 Series, hpcups 3.17.11
hp-check[12795]: info: :Printer status: printer Photosmart_C4700 is idle. enabled since Sáb 07 Abr 2018 11:15:10 WEST ready to print
hp-check[12795]: info: :Communication status: Good
hp-check[12795]: info: :
hp-check[12795]: info: :
hp-check[12795]: info: :--------------
hp-check[12795]: info: :| PERMISSION |
hp-check[12795]: info: :--------------
hp-check[12795]: info: :
hp-check[12795]: info: :No errors or warnings.
hp-check[12795]: info: :
hp-check[12795]: info: :Done.