Does it still happen in a new profile? An easy way to test a new profile is to install Developer Edition and see if it happens there or refresh your existing profile. Make sure you stay signed out of your sync account when testing.

You can right-click and select "Inspect" to open the built-in Inspector with this element selected.

• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/open_the_inspector/
• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/examine_and_edit_html/

You can check in the Rules tab in the right panel in the Inspector what font-family is used for selected text. You can check in the Fonts tab in the right panel in the Inspector what font is actually used because Firefox might be using a different font than specified by the website. If the Fonts tab is hidden, click the Down arrow at the right end.

• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/edit_fonts/

Thank you for the suggestion, wanted to try this first as setting up a new profile isn't something i feel comfortable with.

So I selected "Inspect," didn't see the element to highlight. Tried to find the "rules" tab & can't. but i stumbled into the CSS panel, somehow found Style Editor, where "body, sans-serif { font-family" listed some fonts (helvetica etc), none of which are in my FFox font settings, so it seems ...something... is overriding my choices. i deleted those fonts & the Reader view showed the font i wanted.

But I have to go through all that for Every. Single. Article. -- given the frequency i use Reader, that isn't a good option for me.

Is there a way to permanently change the font setting? i took a look at the page link above & my head is spinning. Again, I'm not an IT professional or anything near it. Do I just bite the bullet & spend a couple hours fooling with the instructions - confusing as they are to me - to change the font?

again, i'd like to point out, this is an issue that *supernova broke,* wasn't a problem in previous FFox version which i'm at the moment very tempted to reinstall.

@zeroknight, thank you for the suggestions, but after spending hours getting supernova configured to *what i already had without effort in previous version,* a refresh doesn't sound like what i want. setting up a new profile, ditto, especially since i have no idea what a sync account is. and Developer Edition doesn't sound like something i'd even remotely want to try.

i did say i'm not an IT professional or anything close -- maybe this response will convince you :-)

I used this as my old userContent.css:

```css @-moz-document url-prefix("about:reader") {

   body.serif {
       font-family: 'EB Garamond 12' !important;
   }
   body.dark{
       --dark-theme-background: rgb(63,51,46);
   }

} ```

Here is my new userContent.css:

```css @-moz-document url-prefix("about:reader") {

   html {
       --font-family: 'EB Garamond 12' !important;
       --dark-theme-background: rgb(63,51,46);
   }

} ``` Unfortunately, with the recent change, there is no way to detect whether the selected font is serif or sans-serif from CSS (the only way I can think of is to parse the --font-family from the html tag). This means that if I don't want Times New Roman as my serif font, and choose a different font in this way, I am not able to use a sans-serif font to read any article at all without going back and inspecting the page.

Now, ideally, "Serif" would mean "--font-family: serif;" and "sans-serif" would mean "--font-family: sans-serif;", and the body would have the .serif or .sans-serif class depending on the font style that the user used, and the user would be able to choose the specific font they want to use themselves without hacking around with userContent.css. These solutions are extremely easy to implement; I don't know why web developers like to assume that there's a finite amount of fonts that users like, and only give the user those options.

(technical details: I'm on Firefox 129.0 from the mozilla.org tarballs, on the Linux distribution "KDE Neon User" based on Plasma 6.1 and Ubuntu 22.04, running Plasma Wayland)