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mozilla-mobile
fenix
Kotlin2018–2024
mozilla-mobile / fenix · Archived

fenix

⚠️ Fenix (Firefox for Android) moved to a new repository. It is now developed and maintained as part of: https://github.com/mozilla-mobile/firefox-android

112Distinct people
159Mentions
1Explicit recommenders
6.4KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

⚠️ Fenix (Firefox for Android) moved to a new repository. It is now developed and maintained as part of: https://github.com/mozilla-mobile/firefox-android

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

I love all of the work that Mozilla do to make the web a better, more privacy focused place. A little time tinge of disappointment though, is that the new Firefox for Android…

2T1Qka0rEiPr used a recommendation phrase. One indexed comment matches. This is a phrase match, not a verdict.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 8:03:49 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year159 dated mentions

Observed mentions: 2018-11-10 16:40:14 UTC to 2024-08-29 17:38:28 UTC.

010203040502018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments20182019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 49 mentions; 1 submissions, 48 comments2020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 42 mentions; 3 submissions, 39 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 24 mentions; 5 submissions, 19 comments20212022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 27 mentions; 2 submissions, 25 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 12 mentions; 3 submissions, 9 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 4 mentions; 1 submissions, 3 comments2024

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC101
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC49148
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC42339
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC24519
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC27225
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC1239
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC413

From the project README

An excerpt from the repository, fetched Nov 12, 2026.

Read the project’s introduction
Firefox for Android Fenix (internal codename) is the all-new Firefox for Android browser, based on GeckoView and Mozilla Android Components. Getting Involved Please read the Community Participation Guidelines and the Bugzilla Etiquette guidelines before filing an issue. This is our professional working environment as much as it is our bug tracker, and we want to keep our workspace clean and healthy. Guide to Contributing (New contributors start here!) Browse our current Issues, or file a security issue. Matrix: #fenix:mozilla.org channel (We're available Monday-Friday, GMT and PST working hours). Related channels: #mobile-test-eng:mozilla.org channel: for UI test automation #perf-android-frontend:mozilla.org channel: for front-end (JVM) performance of Android apps #android-tips:mozilla.org channel: for tips on Android development Check out the project wiki for more information. See our guide on Writing Custom Lint Rules. Localization happens on Pontoon. Please get in touch with delphine (at) mozilla (dot) com directly for more information. Beginners! - Watch out for Issues with the "Good First Issue" label. These are easy bugs that have been left for first timers to have a go, get involved and make a positive contribution to the project! I want to open a Pull Request! We encourage you to participate in this open source project. We love Pull Requests, Bug Reports, ideas, (security) code reviews or any other kind of positive contribution. Since we are a small team, however, we do not have the bandwidth to review unsolicited PRs. Please follow our Pull Request guidelines, or we may close the PR. To make it easier to review, we have these PR requirements: Every PR must have exactly one issue associated with it. Write a clear explanation of what the code is doing when opening the pull request, and optionally add comments to the PR. Make sure there are tests - or ask for help on how the code should be tested in the Issue! Keep PRs small and to the point. For extra code-health changes, either file a separate issue, or make it a separate PR that can be easily reviewed. Use micro-commits. This makes it easier and faster to review. Add a screenshot for UX changes (this is part of the PR checklist) As a small team, we have to prioritize our work, and reviewing PRs takes time. We receive lots of PRs every day, so if you can keep your PRs small, it helps our small team review and merge code faster, minimizing stale code. Keep in mind that the team is very overloaded, so PRs sometimes wait for a very long time. However this is not for lack of interest, but because we find ourselves in a constant need to prioritize certain issues/PRs over others. If you think your issue/PR is very important, try to popularize it by getting other users to comment and share their point of view. I want to file an issue! Great! We encourage you to participate in this open source project. We love Pull Requests, Bug Reports, ideas, (security) code reviews or any other kind of positive contribution. To make it easier to triage, we have these issue requirements: Please do your best to search for duplicate issues before filing a new issue so we can keep our issue board clean. Every issue should have exactly one bug/feature request described in it. Please do not file meta feedback list tickets as it is difficult to parse them and address their individual points. Feature Requests are better when they’re open-ended instead of demanding a specific solution -ie “I want an easier way to do X” instead of “add Y” Issues are not the place to go off topic or debate. If you have questions, please join the #fenix:mozilla.org channel. Please always remember our Community Participation Guidelines Please do not tag specific team members to try to get your issue looked at faster. We have a triage process that will tag and label issues correctly in due time. If you think an issue is very severe, you can ask about it in Matrix. Please keep in mind that even though a feature you have in mind may seem like a small ask, as a small team, we have to prioritize our planned work and every new feature adds complexity and maintenance and may take up design, research, marketing, product, and engineering time. We appreciate everyone’s passion but we will not be able to incorporate every feature request or even fix every bug. That being said, just because we haven't replied, doesn't mean we don't care about the issue, please be patient with our response times as we're very busy. Build Instructions Pre-requisites: Android SDK To run command line tools, you'll need to configure Java: see our how-to guide. Clone or Download the repository: git clone https://github.com/mozilla-mobile/fenix Import the project into Android Studio or build on the command line: ./gradlew clean app:assembleDebug If this errors out, make sure that you have an ANDROID_SDK_ROOT environment variable pointing to the right path. Make sure to select the correct build variant in Android Studio. See the next section. Make sure to select "Default APK" under Installation Options inside Run/Debug configuration: see this bug. Build Variants For general development, we recommend the debug build variant. Here's an explanation of each variant: debug: the default for developers, similar to most other Android apps. It is debuggable, uses a Nightly GeckoView with debug symbols, adds tools like LeakCanary for troublingshooting, and does not strip unused code. nightly: what we ship to the Firefox Nightly channel, using GeckoView Nightly. beta: what we ship to the Firefox Beta channel, using GeckoView Beta. It is more stable than nightly. release: what we ship as Firefox for Android, using GeckoView Release. It is the most stable. nightly, beta, and release are unsigned and debuggable=false by default. If you want these variants to be: automatically signed, see Automatically signing release builds debuggable=true, see Building debuggable release variants Performanc
Read the full README on GitHub

What Hacker News says

42 sources
> Leanplum, location, "device id" Doesn't have access to location and the unique id is specific to leanplum so it can't be tied to anything else. See [1] for an explanation (the source seems to match from my quick look) > GCM Firefox has certain real-time features (like sending tabs) that wouldn't be feasible without cloud messaging. Telegram FOSS and many other apps use workarounds that are less reliable, worse UX and drain battery anywhere from a bit more to HOLY SHIT WHERE DID THOSE 4500mAh GO? (source: Telegram FOSS on my OP3T) If you want to propose a better solution, I'm sure the 3 remaining devs at Mozilla would love to hear it. > Okay, now it's time to refine this in context of "Firefox Klar", "Firefox Focus" or say, the Fenix codebase(s). ... Sure, let's talk about Fenix - what is now available in G Play as the standard "Firefox
Read the rest
for Android". I don't use Klar or Focus, but they use much of the same code, so all of this is quite general. > - Mozilla implemented their own ads distribution system that hijacks google ads on pages and replaces the id with the one that was specifically generated for the web browser The link you provided doesn't make that clear and neither do you. What "id" are you referring to? What is its significance and where in the code is it replaced? > - Mozilla's Safebrowsing uses a generated hash, that is used specifically to identify a single device The link you give makes no sense. The URL at the marked line is the URL from which hashes of unsafe URLs are fetched (for China). The hashes are (anonymized) URLs, not devices, and they are received, not sent. If what you're concerned about is "SAFEBROWSIND_ID" in that string, it is mapped to an implementation-specific not instance-specific identifier, as is clearly required by Google's API [2] and is in fact taken from a the about:config entry "browser.safebrowsing.id" that you can check for yourself only contains something generic like "navclient-auto-ffox". > - The server for both of those hash URLs is hosted by Alibaba in CHINA ... Only for Chinese builds of the engine. See the if statement at [3] and explanation of the config option at [4]. The code you linked simply overrides the default SafeBrowsing API URL for the Chinese market as the original URL is not available there. The browsers treats it identically as the original, so all the client-side privacy guarantees are still there. > > On top of that, FF takes extra measures to protect privacy "just in case". > As my links prove: No, they don't That part of my post was still referring to SafeBrowsing, specifically the part where they separate the cookie jar and inject some extra noise. [5] explains the whole process quite well (it's similar to how HaveIBeenPwned works) > For example, they activate Leanplum's device id specific tracking even if the user is outside the geofences, so they track users even if they already know it's unnecessary. [7] But they're not "tracking" them in any significant way. My first link outlines this quite well. As for why those locales are hard-coded, It's probably because those are the biggest markets and will usually be the first in A/B any rollouts, so using geofences would just be wasteful as they'd always return true anyways. Either way, nothing nefarious there. [1] https://github.com/mozilla-mobile/fenix/blob/b8de7079a963efb... [2] https://developers.google.com/safe-browsing/v4/reference/res... [3] https://github.com/mozilla-mobile/fenix/blob/master/app/src/... [4] https://github.com/mozilla-mobile/fenix/blob/baaa85db804a096... [5] https://feeding.cloud.geek.nz/posts/how-safe-browsing-works-...
In Our Year in Review: How We’ve Made Firefox Faster in 2020
I tend to disagree with your statements. The codebases provide enough evidence that this is not the case. > - Leanplum seems to be there for A/B testing and doesn't have access to anything sensitive. Leanplum has access to at least geolocation and the device id (See [1]), due to their geofencing A/B testing feature. Combine that with an IP and you can uniquely identify any user. Additionally, Leanplum sends its messages via their own Firebase Provider [2]. > - Firebase is partially unavoidable (GCM) Firebase Push Notifications are necessary since Android 10, and only if your application consistently runs in the background. If you have e.g. a download notification with a high priority displayed, your app is allowed to continue to run without any firebase, at all. Source: The Telegram FOSS fork does this, actually. See [3] for details > - G
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oogle Safe Browsing seems to be designed in a way that makes it nearly impossible to violate privacy, even if you wanted to. Okay, now it's time to refine this in context of "Firefox Klar", "Firefox Focus" or say, the Fenix codebase(s). I'm focussing on Fenix here only, because all current Firefox products for mobile rely on it as an engine. (Usually the same metrics are included in Firefox for Desktop, too, but this post would explode this comment; see spywarewatchdog or similar audits for more details on it, which still hasn't been improved over the years by mozilla.) - Mozilla implemented their own ads distribution system that hijacks google ads on pages and replaces the id with the one that was specifically generated for the web browser (after first opening the web browser) [4]. - Mozilla's Safebrowsing uses a generated hash, that is used specifically to identify a single device [5]. - The server for both of those hash URLs is hosted by Alibaba in CHINA, which is certainly a GDPR "violation by the book", as the server is contacted for everyone, not only people that live within China; every time the Browser is online again; even in an interval. (also [5]) - Fenix also adds Tab interactions and sends the data to their telemetry service; including the URL and history of that specific tab [6] > On top of that, FF takes extra measures to protect privacy "just in case". As my links prove: No, they don't. For example, they activate Leanplum's device id specific tracking even if the user is outside the geofences, so they track users even if they already know it's unnecessary. [7] ========= [1] https://github.com/Leanplum/Leanplum-Android-SDK (especially the AndroidSdkCore is relevant here, assuming the discussion of the "most privacy respecting" featureset) [2] https://github.com/Leanplum/Leanplum-Android-SDK/blob/master... [3] https://github.com/Telegram-FOSS-Team/Telegram-FOSS/blob/mas... [4] https://github.com/mozilla-mobile/fenix/blob/5ad714db864bce7... [5] https://github.com/mozilla-mobile/fenix/blob/686f7bd7c65cbaa... [6] https://github.com/mozilla-mobile/fenix/blob/556fea5591acbde... [7] https://github.com/mozilla-mobile/fenix/blob/41a92a8d8b31644...
In Our Year in Review: How We’ve Made Firefox Faster in 2020
> it's where they moved the address bar to the bottom Yup, that's Fenix. By the way, you can switch it back to the top, but the (+) button (new tab) still remains at the bottom, which irks me. I actually just tried and I'm not seeing your issue - but I have different issues (mainly that when I open the browser, the topmost tab can never seem to figure out whether it has a page loaded or it's on the new tab page). By the way, I'm just a fellow user, so don't spend too much effort describing your bug to me, haha. It might be worth reporting it to their bug tracker, though: https://github.com/mozilla-mobile/fenix/issues If your device happens to be a Samsung phone, it should come with a screen recorder (at least on the newest major version of Android)
In Chrome is not the new IE
> Page caching is way too aggressive. It's not acceptable to show days old versions of a website in a new tab. Yet, this happens to me on pretty much all news websites and blogs that I visit. Including HN. I have to reload freshly opened news websites to get the current version. To me this feels like a bug and I hope this is not actually intended behavior (that would be seriously misguided). If this is with collections, apparently it's intentional: https://github.com/mozilla-mobile/fenix/issues/10417
In Firefox Android Build that caused issues is working as intended
Here is the relevant Discourse discussion: https://discourse.mozilla.org/t/add-on-support-in-new-firefo... and the relevant GitHub issue, which was locked due to too many people complaining: https://github.com/mozilla-mobile/fenix/issues/11308 which was closed and moved into this issue, which was locked immediately as this change is... rather unpopular, as is their proposed solution: https://github.com/mozilla-mobile/fenix/issues/14034
In Firefox Android Build that caused issues is working as intended
If that's what the claim was I'd be inclined to agree but extension support was not deceptively and indefinitely dropped in Q3 2019 as the comment talked about. There was Fear extensions would be permanently removed imminently, Uncertainty with how the releases would be scheduled and feature roadmap, and Doubt they'd ever listen to feedback. In reality partial extension support was already there + expansion of support on stable on full support on nightly on the near term timeline at release https://github.com/mozilla-mobile/fenix/issues/14034, the switch on stable FF happened in Q3 2020, and they changed stance after all of the feedback.
In Firefox Android Build that caused issues is working as intended
I got force-upgraded to Fenix a few weeks ago, I had checked out the betas and previews previously and was amazed at how much stuff is still missing or broken: - Most extensions are not supported yet. Looks like we'll at least get this in Nightly soon: - https://github.com/mozilla-mobile/fenix/issues/14034 - Bookmark keywords are missing: - https://github.com/mozilla-mobile/fenix/issues/2497 - https://github.com/mozilla-mobile/fenix/issues/12099 - https://github.com/mozilla-mobile/fenix/issues/12100 - Tab Queue is missing: - https://github.com/mozilla-mobile/fenix/issues/470 - https://github.com/mozilla-mobile/fenix/issues/12338 - Sharing a link from an app directly to another device is missing: - https://github.com/mozilla-mobile/fenix/issues/1523 - https://github.com/mozilla-mobile/fenix/issues/11780 - Collection
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In A new Firefox for Android experience
@ #1: To be clear, I am not a Mozilla employee. So do not take this as a confirmation, I am just quoting the documentation. @ "Fenix only has the two 'data sharing' sections." - You can always untick the checkbox in the crash reporter, see [1]: The data choice in the settings was removed in [2] and tickboxes were added at the same time in [3]. Fenix will also remember you crash reporting choice in the following crashes, you can test this yourself using - warning, this will crash your browser - about:crashparent. Thanks for including your previous message: I think the ban was primarily based on your first message, but that is just my personal opinion. Hopefully you get more details from your report. Sources: [1] https://user-images.githubusercontent.com/4037709/55157721-c... [2] https://github.com/mozilla-mobile/fenix/issues/1264 [3] https
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