blockedbyaddons=false, prints blank page

[Heine Svendsen]

I removed the addon ClassicTheme from FireFox 55.0.3 and I think that's when FireFox started to print a blank page instead of the real content of web pages.

I have found, that changing this line in the prefs.js file from False to True, cures the problem.
user_pref("extensions.e10sMultiBlockedByAddons", true);

But after a closing and starting Firefox a few times, the line goes back to "false".
Why is this?
I cannot find the setting in Firefox, where I can change this in a dialog box.
I have to open the prefs.js file and edit it manually every time this error occurs.

[therube]

The pref change aside, what happens if you restart FF in Safe Mode?
Are pages still blank (regardless of that pref change or not)?

[Heine Svendsen]

Starting in Safe Mode cures the problem. Firefox then prints as normal.
I don't have any add ons installed. But it seeme, that the problem started after removing the add on ClassicTheme.
Could some remaining settings from this add on be the cause of my printing problems?
(I do have three plug-ins installed, but they haven't changed in a long time)

[LIMPET235]

You might like to check in your prefs. for any leftovers.
Open a new blank tab.
Type or copy 'n' paste "about:config" (without the quotes) into the URL bar.
Press "Enter".
Accept the silly "warning" message.
At the top of the next screen, there is a Filter Bar.
Search for classic theme.
Right click to highlight each & select "Reset."
Close & re-open Firefox.

[Heine Svendsen]

There were 4 lines related to ClassicTheme.
They all disppeared after a reset, but printing still gives me just one empty page and an unknown error from Firefox right after the print command.

[LIMPET235]

Have you seen this article yet? May help.
> http://kb.mozillazine.org/Problems_printing_web_pages

[dickvl]

Does disabling hardware acceleration in Firefox work?

Options -> General: Performance:
Remove checkmark: "Use recommended performance settings"
Remove checkmark: "Use hardware acceleration when available"

You need to close and restart Firefox after toggling this setting.

You can also check for issues with multi-process in Firefox.
http://www.ghacks.net/2016/07/22/multi-process-firefox/

[Reflective]

Open about:config and then copy/paste the following into the filter at the top: extensions.e10sBlockedByAddons If it's set to false. double click it to set it to true.

[LIMPET235]

Check this article...
> ref; > http://kb.mozillazine.org/Preferences_not_saved