Firefox UI font size

[sgage]

I am trying to figure out how to increase the font sizes of the UI elements (tabs, toolbars, menus, etc.) in Firefox. (Also Thunderbird). Most other programs respect the KDE font settings, but not FF and TB, and the fonts are just too small for my tired old eyes.

There used to be an extension that enabled one to tweak such things, but it was never updated for the new extension architecture that FF adopted some time ago.

Can anyone help me out?

TIA

[chimak111]

Create ~/.config/gtk-3.0/settings.ini if it doesn't already exist.

Mine looks like this:

[Settings]
gtk-application-prefer-dark-theme=false
gtk-button-images=1
gtk-cursor-theme-name=breeze_cursors
gtk-fallback-icon-theme=LoginIcons
gtk-font-name=Hack Regular 12
gtk-icon-theme-name=breeze
gtk-menu-images=1
gtk-primary-button-warps-slider=0
gtk-theme-name=myBreeze-Dark
gtk-toolbar-style=GTK_TOOLBAR_TEXT

For the current purpose, gtk-font-name=Hack Regular 12 is relevant.

[sgage]

Create ~/.config/gtk-3.0/settings.ini if it doesn't already exist.

Mine looks like this:

[Settings]
gtk-application-prefer-dark-theme=false
gtk-button-images=1
gtk-cursor-theme-name=breeze_cursors
gtk-fallback-icon-theme=LoginIcons
gtk-font-name=Hack Regular 12
gtk-icon-theme-name=breeze
gtk-menu-images=1
gtk-primary-button-warps-slider=0
gtk-theme-name=myBreeze-Dark
gtk-toolbar-style=GTK_TOOLBAR_TEXT

For the current purpose, gtk-font-name=Hack Regular 12 is relevant.

Thank you, friend! KDE just became usable for me!

[chimak111]

Thank you, friend! KDE just became usable for me!

You're welcome! I forgot to mention that all your gtk3 apps will be affected the same way unless you specifically override these settings.

[BYTEMOTION]

Create ~/.config/gtk-3.0/settings.ini if it doesn't already exist.

Mine looks like this:

[Settings]
gtk-application-prefer-dark-theme=false
gtk-button-images=1
gtk-cursor-theme-name=breeze_cursors
gtk-fallback-icon-theme=LoginIcons
gtk-font-name=Hack Regular 12
gtk-icon-theme-name=breeze
gtk-menu-images=1
gtk-primary-button-warps-slider=0
gtk-theme-name=myBreeze-Dark
gtk-toolbar-style=GTK_TOOLBAR_TEXT

For the current purpose, gtk-font-name=Hack Regular 12 is relevant.

how to create Create ~/.config/gtk-3.0/settings.ini if does not exist, I recieve a message error

I type ( ~/.config/gtk-3.0/settings.ini ) file does not exist

[claydoh]

It is a text file, you can use Kate to create a file, and save it to the specified file name/location.

The ~ symbol is simply shorthand for /home/<your-username>, so /home/<your-username>/.config/gtk-3.0/settings.ini