Hi Mary, Yes, you **should be able to resize the Firefox window** on Linux using your mouse. If it’s only allowing one fixed size, a few things could be causing this: 1. **Window manager limitations** – Some Linux desktop environments (like GNOME, KDE, or tiling window managers) may restrict resizing for certain windows. 2. **Maximized or full-screen mode** – If the window is maximized, you can’t resize until you restore it to a normal window. 3. **Firefox bug or profile issue** – Try restarting Firefox or creating a new profile to see if the problem persists. 4. **Check for extensions/themes** – Occasionally, a theme or extension can interfere with window resizing. **Tip:** Try pressing **Alt + Space** (or right-click the title bar) and select “Resize” to manually adjust the window. This should help you regain normal window resizing.