1974569 - Deep Links stopped working on 140.0

Status: VERIFIED FIXED

(Firefox for Android :: App Links, defect, P1)

Description

[Lucas Queiroz]

Attachment: Screen_Recording_20250628_070415_Firefox.mp4

User Agent: Mozilla/5.0 (Android 15; Mobile; rv:140.0) Gecko/140.0 Firefox/140.0

Steps to reproduce:

Try to open any external app intent from Firefox on Android:

• mailto:
• tel:
• instagram://
• obsidian://

Actual results:

A blank page opens, or nothing at all - stays on the same webpage.

Expected results:

The user should be redirected to the app that has that intent.
When clicking "Open in App", it does redirect, but shouldn't need that to open an intent.

Comment 2

[BugBot [:suhaib / :marco]]

The bug has a release status flag that shows some version of Firefox is affected, thus it will be considered confirmed.

Comment 3

[BugBot [:suhaib / :marco]]

The bug is marked as tracked for firefox140 (release), tracked for firefox141 (beta) and tracked for firefox142 (nightly). However, the bug still isn't assigned.

:royang, could you please find an assignee for this tracked bug? If you disagree with the tracking decision, please talk with the release managers.

For more information, please visit BugBot documentation.

Comment 4

[Donal Meehan [:dmeehan]]

Setting Fx140 to Fixed since the regressor was backed out from release. A backout from beta will follow to "fix" this in Fx141.
https://bugzilla.mozilla.org/show_bug.cgi?id=1929028#c14

A follow-up patch is expected to fix forward in Fx142.

Comment 5

[Polly [:polly]]

raised 1974753 to cover the mailto: case, which is a separate issue unaffected by the backout.

Comment 6

[Roger Yang [:royang]]

Note that the functionality for the follow is not affected when user is tapping on links:

• instagram://
• mailto:
• tel:
• twitter://

Only when user manually typed in/paste in the URL. This is caused by a check to deny redirecting to external application when user is typed in a URL, we assume that they want to browse to the site in FIrefox Android.

However, there are some cases (web extensions for example) that wants to redirect to their application by opening a new tab (which count as direct navigation) with a specific intent.

Comment 7

[Roger Yang [:royang]]

Attachment: Bug 1974569 - Allow app links direct navigation to redirect to external application.

Comment 9

[Pascal Chevrel (relman team) -> :pascalc]

Fixed in Beta by backout

Comment 10

[halleck1]

(In reply to Donal Meehan [:dmeehan] from comment #4)

Setting Fx140 to Fixed since the regressor was backed out from release. A backout from beta will follow to "fix" this in Fx141.
https://bugzilla.mozilla.org/show_bug.cgi?id=1929028#c14

A follow-up patch is expected to fix forward in Fx142.

Does the above mean the 140 version will have a minor release with the fix included (via backout)?

Comment 11

[Donal Meehan [:dmeehan]]

(In reply to halleck1 from comment #10)

Does the above mean the 140 version will have a minor release with the fix included (via backout)?

Yes, 140.0.3 will include the backout fix and should start to rollout on 2025-07-01

Comment 12

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/ccc96e77f3a8
https://hg.mozilla.org/integration/autoland/rev/2bdf09b0b0c1
Allow app links direct navigation to redirect to external application. r=android-reviewers,pollymce,tthibaud

Comment 13

[[e-mail]]

https://hg.mozilla.org/mozilla-central/rev/2bdf09b0b0c1

Comment 14

[Vasilica Tamas (Android QA) [:vtamas]]

Attachment: mailto.jpg

This issue is verified as fixed on Firefox for Android Nightly 142 (2025-07-03), Firefox 141 beta 5 and Firefox 140.0.3 using Samsung S24 Ultra (Android 15) and Pixel Tablet (Android 15). Confirming that when manually typing or pasting an external link the "Open in [App]" prompt is successfully displayed and successfully redirects the user to the intended app.

Comment 15

[Acasandrei Beatrice (needinfo me)]

(In reply to Pulsebot from comment #12)

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/ccc96e77f3a8
https://hg.mozilla.org/integration/autoland/rev/2bdf09b0b0c1
Allow app links direct navigation to redirect to external application.
r=android-reviewers,pollymce,tthibaud

Perfherder has detected a devtools performance change from push 2bdf09b0b0c170deabd5eee5353d8657e4da8754.

If you have any questions, please reach out to a performance sheriff. Alternatively, you can find help on Slack by joining #perf-help, and on Matrix you can find help by joining #perftest.

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)
4%	damp custom.netmonitor.exportHar	macosx1470-64-shippable	e10s fission stylo webrender	622.32 -> 596.92

Details of the alert can be found in the alert summary, including links to graphs and comparisons for each of the affected tests.

If you need the profiling jobs you can trigger them yourself from treeherder job view or ask a performance sheriff to do that for you.

You can run all of these tests on try with ./mach try perf --alert 45904

The following documentation link provides more information about this command.

Comment 16

[Daniel Holbert [:dholbert]]

Note just to explain something that's otherwise a bit confusing about comment 0 vs. later stuff in this bug:

• Comment 0 seems to show the user using https://www.w3docs.com/snippets/html/how-to-create-mailto-links.html as an example with mailto: links.
• The user does tap a mailto link near the start of the video, and it doesn't work (despite comment 6 where royang mentioned this works correctly for tapped links). Tapping that link does consistently work correctly for me, with a freshly installed Nightly from when this bug was filed. I think the issue is that the user in comment 0 had previously tapped "Cancel" which does indeed prevent subsequent taps from working, as discussed in bug 1974753.