The lastest version of Firefox / Nightly seems to have changed what happens when you nudge your central mouse wheel, intending to move down a Web page. It seems to be set up for iPads now, when users are used to ‘jumping’ down the screen in pseudo-frames. But it’s very annoying to jump like that on a desktop, when what you’re used to using is a gentle nudge. Here’s how to fix the problem…

1. Type about:config in the browser’s top Web address bar and press Enter.

2. A big list of settings appears. Type wheel in the search box that sits above these settings. The list is filtered to show only the wheel settings.

3. Look for the setting Double-click the mousewheel.default.delta_multiplier_y. Double-click on it. Changing its setting from 100 to 30 worked for me.