Yes, you can change the default font size in Mozilla Firefox by following these steps:
- Open Firefox and click on the menu button (three horizontal lines) in the top-right corner of the browser window.
- Click on "Options" in the menu.
- In the Options tab, go to the "Language and Appearance" section.
- Under the "Fonts and Colors" section, click on the "Advanced" button.
- In the "Fonts" dialog box, you can adjust the default font size by selecting the desired font size from the "Size" drop-down menu.
- Click the "OK" button to save the changes.
- Restart Firefox for the changes to take effect.
Alternatively, you can also use keyboard shortcuts to change the font size temporarily. Press and hold the "Ctrl" key on Windows or the "Command" key on Mac, and then press the "+" key to increase the font size or the "-" key to decrease it.