Copy/Paste : about:preferences#general into the Address Bar and Enter

Go down to Browsing then untick Search For Text When Start Typing

Please let us know if this solved your issue or if need further assistance.

There used to be an extension (searchhotkeys) to disable this feature, but that is no longer working even if it would still be available.

These special keys to search for links should only work if a text input field doesn't have focus.

Are searches initiated for you when you are typing text in an input area?

Many thanks for the replies! The webpage I referred to was actually Google. The quick search does not trigger when the usual search input field is in focus. However, once the page recognizes the formula input, it brings up a calculator which also accepts text input. It is in this field that encountered the reported problem. Basically you cannot type divide into the calculator.

Many thanks for the reply. The 'search for text when start typing' box was unchecked in the options menu when I encountered the problem.

From a comment in this bug: try the Shortkeys (Custom Keyboard Shortcuts) for Firefox add-on and configure / to do nothing in its Behavior drop-down. This works for me on 57, but I haven’t tested the calculator behavior.

Don’t forget to reload the tabs. You may need to restart the browser too.

Tonnes said

From a comment in this bug: try the Shortkeys (Custom Keyboard Shortcuts) for Firefox add-on and configure / to do nothing in its Behavior drop-down. This works for me on 57, but I haven’t tested the calculator behavior. Don’t forget to reload the tabs. You may need to restart the browser too.

Thanks for the link to the bug ticket! It's very informative to know that there are actually two hard-coded activators for the quick search function. I will give the addon a try!