Browser / Version
Firefox Preview Nightly 191124 (🦎: 72.0a1-20191119043902)

Operating System
Samsung Galaxy S8 (Android 9) - 1440 x 2960 pixels, 18.5:9 ratio (~570 ppi density)

Steps to reproduce:

1. Navigate to: https://login.matrix.ms.com/public/login-email/webapp/entry?uri=/eqr/article/webapp/7c64f03e-0ba8-11ea-b68a-eed409965aa8
2. Fill in the e-mail address field.
3. Tap the Verify button.

Expected Behavior:
The next page is loaded.

Actual Behavior:
Nothing happens.

Notes:

1. Screenshot attached.
2. The issue is NOT reproducible with ETP OFF.

Breakage as a result of strict content blocking. Arturo, can you please have a look?

Sure, I can open an issue Android Components to verify. Do you know if this issue is reproducible on desktop?

Yes, it is. All you have to do is to set content blocking to strict, or test in a private browsing window.

@ehsan I filed this bug on Android Components repository to take a look

Sergiu, is this now working for you as well? I don't have a valid email, but when I enter one in strict mode it says "You have entered an invalid email", so I'm guessing it's working now.

Yes, this is still reproducible on my side.
http://prntscr.com/rulbke

Firefox Preview Nightly 200405 (🦎: 76.0a1-20200403063228)
Samsung Galaxy S8 (Android 9) - 1440 x 2960 pixels, 18.5:9 ratio (~570 ppi density)

Strange, I'm able to click the verify button to get an "you have entered an invalid email address" message on Fenix nightly on my phone with strict ETP on. Do you need to try with a legitimate email address to reproduce the issue?

We do not have a legitimate e-mail address, unfortunately.
However, it I let the e-mail field empty and tap the Verify button, I get the error.

http://prntscr.com/rw5svc

Note: I tried with a clean instance of Fenix Nightly (Cleraed the app's data)

Apparently, the issue is not reproducible on the same build*, on OnePlus 6 (Android 9).
But it is reproducible on Nokia 6.1 (Android 10), Samsung Galaxy S8 (Android 9), Samsung Galaxy S6 (Android 7), Huawei P20 Lite (Android 8), Huawei P10 (Android 9).

*Firefox Preview Nightly 200405 (🦎: 76.0a1-20200403063228)

Also, this is the Console output, before, during and after taping on the button:
http://prntscr.com/rw68zv

Hmm, I cannot reproduce it on my Samsung Galaxy S7 Edge :(

This might be a pain to test, but could you check it on an affected device for me, Sergiu?

If you add the about:config value urlclassifier.trackingSkipURLs, set it to ssl.google-analytics.com, does reloading that page un-break attempts to login?

If so, we should be able to avoid this by shimming that script similarly to the suggestion in https://bugzilla.mozilla.org/show_bug.cgi?id=1487072#c2

Looks like your suggestion fixes the issue, Tom!

Alright, thanks! Then this is another case where at least pretending the analytics script loaded (or stubbing it out a bit) will help, like in bug 1487072.

The layout has changed and the issue no longer reproduces.
URL: https://login.matrix.ms.com/public/login/webapp/html/main/public_Loginhtml?uri=%2Fmatrix%2Fportal%2Fdocs%2F&xfofr=#/usernamefirst_login
https://prnt.sc/y0znc8

Tested with:
Browser / Version: Firefox Nightly 210201 (🦎 87.0a1-20210129095945)
Operating System: Samsung Galaxy S8 (Android 9) - 1440 x 2960 pixels, 18.5:9 ratio (~570 ppi density), Huawei P20 Lite (Android 8.0.0) - 1080 x 2280 pixels, 19:9 ratio (~432 ppi density)