Hey there! I totally get where you're coming from. The font size units in the Firefox settings page are indeed pixels. But no worries, there's a trick you can use to set your font sizes in points. You can head to the "about:config" page in your Firefox browser, search for "layout.css.devPixelsPerPx," and adjust that setting to your preference. This way, your text will show up consistently across different screens. Just be careful while tweaking settings there, and remember, it's always a good idea to back up things before making changes. Hope this helps you get your fonts just right!

WARNING from the moderator team: Changing Firefox preferences from the about:config page can sometimes break Firefox or cause strange behavior. You should only do this if you know what you're doing. Please read Firefox Advanced Customization and Configuration Options to learn more.

You may be able to set font sizes in points by creating a file userContent.css.

The current value of layout.css.devPixelsPerPx is -1. What does "adjust that setting to your preference" mean? What (fixed) value of layout.css.devPixelsPerPx will cause Firefox to interpret the font size numbers in the settings page as points rather than pixels. A fixed ratio won't solve my problem of using the same point size on screens with different pixel densities.

Hey there! You're right that the font size units in Firefox's settings page are in pixels. To make them show in points and maintain the same size on different screens, you can tweak a setting. Type "about:config" in your Firefox browser's address bar, search for "layout.css.devPixelsPerPx," and set it to a specific value (for example, 1.25). This will adjust the font sizes to your preference. Just remember, be careful with these settings and back up things before making changes. Hope this helps you achieve the font size you want!

I don't see that applying a multiplier to the font sizes will help me. Every time I switch between the external monitor and the laptop's own screen, which have different pixel densities, I would have to go to the about:config page, search for "layout.css.devPixelsPerPx", and change the ratio. This isn't really any simpler than changing the font sizes in the settings page.

I think this is a design error in Firefox. With the large number of different types of screen with different sizes and pixel densities now available, pixel number isn't a useful measure of font size for users. Firefox should be using point size, as used by most other applications, and in particular the KDE system settings page. Alternatively it could give a choice of units or allow default to the system font size settings.

Hi,

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