[Bug]: Unable to load Twitter in Fenix Nightly only in Private Browsing mode

[Fanolian]

Steps to reproduce

1. Open Private Browsing mode in Fenix.
2. Go to any Twitter page, e.g. https://www.twitter.com/firefox/.
3. Click cancel when the prompt of opening link in app appears.

Expected behaviour

The page should be loaded in Fenix successfully.

Actual behaviour

A prompt about opening the link in app appears. Clicking cancel does not load the link in Fenix. It shows a blank page instead.
In non-PB mode, I can load the link properly.

Video of the issue:

Fenix.PB.mode.Twitter.compressed.mp4

(Or original quality 66MB: https://giant.gfycat.com/GargantuanPossibleAsiandamselfly.mp4)

Device name

Google Pixel 4a

Android version

Android 13 October 2022 update

Firefox release type

Firefox Nightly

Firefox version

108.0a1 (Build #2015913675), 408d15a+ AC: 108.0.20221103143443, 5cc49c0 GV: 108.0a1-20221103095349 AS: 94.3.2 2022-11-03T17:07:17.965436

Device logs

No response

Additional information

I cannot reproduce the issue in non-PB mode. (Shown in the last part of the attached video)
I cannot reproduce it in PB mode of Fenix Release 106.1.0 (Build #2015909131), 71ca6c1+ AC: 106.0.5, 5f06485fc3 GV: 106.0-20221010181815 AS: 94.2.1 2022-10-11T01:08:43.974343

It is reproducible either Open links in apps in Settings is enabled or not.
It is reproducible with all addons disabled.
I have tried turning Enhanced Tracking Protection off and deleting browsing data, except history and site data.

I do not have Twitter app installed. I tried installing it (But without logging on) but the issue persists.

┆Issue is synchronized with this Jira Task
┆Link To Issue: https://mozilla-hub.atlassian.net/browse/FNXV2-21934

[AdinaPetridean]

@Fanolian thank you for your report! I was able to reproduce this issue on Firefox Nightly 108.0a1- 7/11 with One plus 9 Pro (Android 12). However I only reproduced it after reloading the twitter page (not on the first try).

[Fanolian]

I tried Wikipedia which triggers open-in-app prompts. It works but the address given in the prompt is https://, not intent:// like Twitter. I don't know any other sites that also open an intent:// address.

[shtstorm]

The problem is with any Twitter link and any embedded Twitter post on any page. If you start with a page in Private Browsing mode and click on a Twitter link, there will be one or more "intent" pop ups and the page would fail to load.

For instance, open this page in PB mode and click on this link: Firefox 🔥 (@firefox) / Twitter

This is probably a higher priority issue because Twitter is broken as of now in permanent PB mode.

[yoasif]

This issue is now present in beta - we are seeing reports elsewhere.

It is also happening in non-private browsing mode in Nightly, so I think this is a pretty serious issue.

[rocketsroger]

More investigation is needed, but this could be related. Tested, unrelated.

[plwt]

User feedback: https://support.mozilla.org/en-US/questions/1397340

[plwt]

User feedback: https://support.mozilla.org/en-US/questions/1397560

[Fanolian]

It doesn't work in non-PB mode now. Loading a twitter page will open Google Play Store.

[t-p-white]

@Fanolian thank you for your report! I was able to reproduce this issue on Firefox Nightly 108.0a1- 7/11 with One plus 9 Pro (Android 12). However I only reproduced it after reloading the twitter page (not on the first try).

Confirm this is also the case while testing on Pixel 7 (Android 13)

It doesn't work in non-PB mode now. Loading a twitter page will open Google Play Store.

Thanks @Fanolian, also confirmed on Pixel 7 (Android 13)

[boek]

@rocketsroger @t-p-white - @zmckenney and I fell into investigating this on Friday (The last work day before Thanksgiving break) and we found out that this may be caused by cookie banner handling set to Enabled (Accept or accept all). It appears that whatever heuristics we use to detect cookie banners thinks that the Open in App banner is one. Accepting it redirects to https://twitter.app.link which then takes you to the play store.

[rocketsroger]

@rocketsroger @t-p-white - @zmckenney and I fell into investigating this on Friday and we found out that this may be caused by cookie banner handling set to Enabled (Accept or accept all). It appears that whatever heuristics we use to detect cookie banners thinks that the Open in App banner is one. Accepting it redirects to https://twitter.app.link which then takes you to the play store.

Thanks Jeff, this is a good observation.

[rocketsroger]

I can confirm that I can reproduce with an older Nightly and latest Beta but not with latest Nightly build. @Fanolian, @yoasif and @shtstorm, can you please help me confirm this finding? Thanks

[rocketsroger]

Adding QA to confirm that with latest Nightly this is not reproducible. Thanks

[rocketsroger]

This said, I'm still trying to figure out what's causing the problem in Beta.

[rocketsroger]

Confirmed @boek's and @zmckenney's investigation. This issue is related to Cookie Banner Protection. Thanks

[Fanolian]

Confirm that this can't be reproduced in latest Nightly, PB or non-PB mode.

[rocketsroger]

Bugzilla issue created.

[AdinaPetridean]

Verified as fixed on the latest Nightly 109.0a1 from 29/11 with Motorola Moto G9 plus (Android 11). This issue is no longer reproducible in normal or private browsing.

twitter.mp4

[kbrosnan]

This is being tracked in the upstream bug.