Question about userContent.css and blank page backgrounds

Big Al

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Dec 11, 2017, 4:53:51 PM12/11/17

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I found documentation on how to change the color of both the about:blank
and about:newtab page backgrounds. userContent.css would contain the
following:

@-moz-document url("about:newtab") {
body {
background-color: #C9FFC9 !important; /* pale green */
color: black !important;
}
}

@-moz-document url("about:blank") {
body {
background-color: black !important;
color: black !important;
}
}

In playing with the colors in about:blank I tried a yellowish or manila
color that kinda worked but finally went to the black as it shows above.

The only problem is that occasionally I pull up a website that starts
with this old yellowish background, and it stays there until Firefox
downloads more of the webpage and then I get the right background as the
designer wanted it. But it's yellow for that 1-3 seconds depending of
load speed.

Also there are a few sites that oddly don't have any background color
specified, the page downloads and I get all the info and ads and
logos/images but this yellowish background persists.

I found one site that does not change the background and looked at the
source and sure enough there is no bgcolor specs.:
<html>
<head>
<title>Appointment Reminder Confirmation</title>
</head>
<body>
<table style="width: 100%; height: 100%;">
<tr> etc etc etc

I can't give you a link since this one is a confirmation for a doctor
appointment and I don't want 100's of people confirming it. :-)

Question is: Where is this yellow background coming from. Is there
some other about:??? that I can set to get rid of it and set it back to
white? Luckily it's not an offensive lime green but white would sure
be better.

Dave Royal

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Dec 12, 2017, 2:24:00 AM12/12/17

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Big Al <Bi...@invalid.com> Wrote in message:
><snip>

> logos/images but this yellowish background persists.
>

> Question is: Where is this yellow background coming from. Is there
> some other about:??? that I can set to get rid of it and set it back to
> white? Luckily it's not an offensive lime green but white would sure
> be better.
>

How odd. Maybe it's cached. Does it persist if you clear the
cache? Or reload about:blank bypassing cache? I'm surprised
about:blank is an actual page that can be styled, though.

ISTR reading that if you open a site in a new tab it starts with
about:blank - but that was Android. And I've known sites that
lose an applied style when you hit 'back' (which would the bf
cache) though I think that's a bug.

Your post reminded me that I styled about:home in userContent.css,
and it's stopped working since 57.
--
(Remove numerics from my email address)

Ocalab

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Dec 12, 2017, 1:08:26 PM12/12/17

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Where did you find that documentation? Please share it - or (preferably
do both) tell us what you searched for. It is not so easy to find those...

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If this messages and others are off-topic,
disconsider that part of it, or ask it to be
moved to another group. If someone replied
here, my opinion is that there is no problem
with that - something that is really rare, IMO.

Big Al

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Dec 12, 2017, 1:10:38 PM12/12/17

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Adding about:home to the userContent.css I was able to change the
background in about:home. So if you want, you can do that much.

I've cleared the cache a few times.
And https://www.gosquared.com/global/windows/10/#launch background is
this yellowish color I can't drop.

It is something in the profile. I created a new profile and the above
link comes up with a all white background. So I guess I'll just try
dropping a few things and see where I lose it. At least now I'm onto
something. All my settings are synced so maybe that will bring back
just settings and not cache.

If I find something I'll post it. Thanks.

Big Al

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Dec 12, 2017, 1:10:54 PM12/12/17

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On 12/12/2017 02:23 AM, Dave Royal wrote:

prefs.js or about:config. browser.display.background_color was set to
the yellowish color. Changed it to #FFFFFF white and all is great.
I never set it but something obviously did.

Big Al

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Dec 12, 2017, 1:13:40 PM12/12/17

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It was probably someone's post on this newsgroup.

5

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Dec 12, 2017, 10:58:42 PM12/12/17

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On 12/11/2017 01:59 PM, Ocalab wrote:
> Em 11-12-2017 19:33, Big Al escreveu:
>> I found documentation on how to change the color of both the about:blank
>> and about:newtab page backgrounds. userContent.css would contain the
>> following:
>>
>> @-moz-document url("about:newtab") {
>> body {
>> background-color: #C9FFC9 !important; /* pale green */
>> color: black !important;
>> }
>> }
>>
>> @-moz-document url("about:blank") {
>> body {
>> background-color: black !important;
>> color: black !important;
>> }
>> }

....

> Where did you find that documentation? Please share it - or (preferably
> do both) tell us what you searched for. It is not so easy to find those...

<https://superuser.com/questions/318912/how-to-override-the-css-of-a-site-in-firefox-with-usercontent-css#319322>
covers it.

I use about:blank as FF's start, home, and newtab pages, and often use a
bookmarklet to turn it black after it loads.

I just copy/pasted Big Al's code into userContent.css ... it works.

The line
color: black !important;
appears redundant. It works the same with or without it.

Dave Royal

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Dec 13, 2017, 2:28:17 AM12/13/17

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5 <fi...@kmail.com> Wrote in message:

I still refer to dbaron's post for alternative @moz-document forms
https://tinyurl.com/per-site-stylesheet-rules

To use userContent.css on Firefox for Android you need root
access. The Stylus addon mostly works on Android BTW, but
webextensions cannot change about: pages.

Big Al

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Dec 13, 2017, 12:46:27 PM12/13/17

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On 12/12/2017 10:57 PM, 5 wrote:
> The line
> color: black !important;
> appears redundant. It works the same with or without it.

Now that you mention it, you're right. A blank page with no text
doesn't need to have the text color set to black.

EE

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Dec 14, 2017, 3:10:52 PM12/14/17

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To change the default body background (but not override), I used this in
userContent.css:
/* Change default backgrounds */
body {background-color: #FFE0C0;}

That gives a beige background.