Firefox 138 release information

Disclaimer

The following information is intended for members of the Mozilla Support community for the purpose of supporting users in the Mozilla Support platform. Mozilla Support is a community of enthusiastic volunteers and employees trying to support Mozilla's users around the globe. You can join us by contributing through the following ways:

Release notes

Bug & feedback boards

Dot releases

Platform	Version	Release date	Notable fixes	Unresolved
Firefox Desktop	138.0.1	May 1, 2025	bug1963537, bug1961710	-

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Content in this page is being updated periodically as we're rolling out the release.

What's new in Firefox 138

Firefox Desktop

Smart Tab Groups
Description:	How to use the smart tab grouping feature, which is an experimental feature in 138.
Content request:	https://bugzilla.mozilla.org/show_bug.cgi?id=1953899
KB article:	https://support.mozilla.org/kb/how-use-ai-enhanced-tab-groups	New article

Accuweather update
Description:	An update to the weather forecast article
Content request:	https://bugzilla.mozilla.org/show_bug.cgi?id=1963191
KB articles:	https://support.mozilla.org/kb/get-your-local-weather-forecast-firefox-address-bar	Article update

Firefox profile management (progressive roll out)
Description:	Firefox profile management
Content request:	https://bugzilla.mozilla.org/show_bug.cgi?id=1952062
KB articles:	https://support.mozilla.org/kb/profile-management	Article update

Firefox for Android

Download manager enhancement
Description:	Enhancement on the Android's download manager feature
Content request:	https://bugzilla.mozilla.org/show_bug.cgi?id=1961695
KB article:	https://support.mozilla.org/kb/downloads-firefox-android	Article update is in progress

Bookmarks enhancement
Description:	Enhancement on ability to sort bookmarks on Android
Content request:	https://bugzilla.mozilla.org/show_bug.cgi?id=1961693
KB article:	https://support.mozilla.org/kb/add-delete-and-view-bookmarked-webpages-firefox-android	Article update is in progress

Firefox for iOS

Known studies/experiments

Escalation

TBD

Known issue(s)/Trending topic(s)

Known incident(s)

New tab page blank even when set to Firefox Home in 138.0
Description:	Some users experience an issue with the new tab is showing blank page despite settings being set to Firefox Home.
Status:	Ongoing
Product(s) impacted:	Firefox Desktop 138
Associated bug:	https://bugzilla.mozilla.org/show_bug.cgi?id=1963537
Resolution/workaround:	The current workaround is to create a new profile

Youtube stops loading due to a syntax error on the latest version of firefox.
Description:	Users are seeing a blank page. Individual videos load if you have the URLs on hand, but nothing else on the page will load, and the videos will eventually time out.
Status:	Ongoing
Product(s) impacted:	Firefox Desktop 138
Associated bug:	https://bugzilla.mozilla.org/show_bug.cgi?id=1963511
Resolution/workaround:	See https://bugzilla.mozilla.org/show_bug.cgi?id=1963511#c32

Support/Firefox138

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