If you open the Firefox inspection window, right-click any element on a webpage and select Inspect. Alternatively, use the keyboard shortcut Ctrl+Shift+C (Windows/Linux) or Cmd+Option+C (Mac). You can also access it via the menu button (three horizontal lines) -> More Tools -> Web Developer Tools.
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If you open the Firefox inspection window, right-click any element on a webpage and select Inspect. Alternatively, use the keyboard shortcut Ctrl+Shift+C (Windows/Linux) or Cmd+Option+C (Mac). You can also access it via the menu button (three horizontal lines) -> More Tools -> Web Developer Tools.
Does it show any errors?