Hi,

to prevent user data loss when filling out forms, we’ve disabled the Backspace key as a navigation shortcut for the back navigation button. To re-enable the Backspace keyboard shortcut, you can change the about:config preference browser.backspace_action to 0. You can also use the recommended Alt + Left arrow (Command + Left arrow on Mac) shortcut instead.

See also "Changed" in the release notes.

• https://www.mozilla.org/en-US/firefox/87.0/releasenotes/
• https://www.mozilla.org/en-US/firefox/88.0/releasenotes/

Was I supposed to be born knowing what the hell this sentence means????s ---> To re-enable the Backspace keyboard shortcut, you can change the about:config preference browser.backspace_action to 0

Was I supposed to be born knowing what the hell this sentence means????s ---> To re-enable the Backspace keyboard shortcut, you can change the about:config preference browser.backspace_action to 0

No, it's definitely acquired knowledge.

about:config is an advanced configuration manager. More info in this article: Configuration Editor for Firefox

To break it down:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

(2) In the search box in the page, type or paste backs and pause while the list is filtered -- should look like

(3) Double-click the browser.backspace_action preference to display an editing field, and change the value to 0 then press Enter or click the blue check mark button to save the change.

For reference, this setting tells Firefox, if you press Backspace outside of a text editing field, to:

• 0 = Go "Back" in history
• 1 = Page Up
• 2 = ignore the keypress (default)

Success?