Yesterday, the team behind the popular Firefox browser released a new version of the product. Firefox 61 is not available with a number of improvements and new features, which include Tab Warming. Here is how to disable it if you are not happy with the new behavior of the browser.
Tab Warming is a new feature of Firefox 61 which tracks the user's mouse cursor and starts rendering content inside a tab whenever the user hovers the mouse over the tab in the tab row. This makes Firefox display the tab content much faster when the user switches to the tab, especially for tabs which were restored from a previous browsing session. Also, this makes the browser to switch between tabs faster. Tab Warming is enabled by default in Firefox.
However, some users complain that Tab Warming causes some sites to have noticeable lags before switching to the tab.
To disable Tab Warming in Firefox, do the following.
- Open a new tab and enter the following text in the address bar:
Confirm that you will be careful if a warning message appears for you.
- Enter the following text in the search box: browser.tabs.remote.warmup.enabled.
- Set this value to false to disable the feature.
- Setting it back to true will re-enable the Tab Warming feature in Mozilla Firefox.
I recommend you to disable Tab Warming only if you have issues with tab switching.
Modern versons of the Firefox browser come with a new user interface, codenamed "Photon", and features a new engine "Quantum". It was a difficult move for developers, because the browser drops support for XUL-based add-ons completely. All of the classic add-ons are deprecated and incompatible, and only a few have moved to the new WebExtensions API. Some of the legacy add-ons have modern replacements or alternatives. Unfortunately, there are plenty of useful add-ons which have no modern analogs. See