Before I have used the code below, but it doesn't work anymore with firefox update.
from selenium.webdriver.firefox.firefox_profile import FirefoxProfile
firefoxProfile = FirefoxProfile()
firefoxProfile.set_preference('permissions.default.image', 2)
I also tried this one below, it seems good but is there a way to disable images without add-on or 3rd party tools?
from selenium import webdriver
firefox_profile = webdriver.FirefoxProfile()
firefox_profile.add_extension(folder_xpi_file_saved_in + "\\quickjava-2.0.6-fx.xpi")
firefox_profile.set_preference("thatoneguydotnet.QuickJava.startupStatus.Images", 2) ## Turns images off