1903659 - web.telegram.org - Can't make video and voice calls (see comment 14 for status)

Status: ASSIGNED

(Web Compatibility :: Site Reports, defect, P2)

Description

[Ksenia Berezina [:ksenia]]

Environment:
Operating system: Android 13
Originally reported Firefox version: Firefox Mobile 116.0
Last reproduced with the following UA: Mozilla/5.0 (Android 14; Mobile; rv:126.0) Gecko/126.0 Firefox/126.0
Platforms reproduced on: android

Steps to reproduce:
I can make call through telegram web with chrome.
But there's no option in Firefox

Actual Behavior:
can't make call

Created from https://github.com/webcompat/web-bugs/issues/124957

Comment 1

[Ksenia Berezina [:ksenia]]

Reproducible on desktop as well.

Comment 2

[Jeff Muizelaar [:jrmuizel]]

I tried making a call with Chrome user agent and it failed. The option to make a call does work in Safari

Comment 3

[Jeff Muizelaar [:jrmuizel]]

I believe Daniel was going to look at this

Comment 4

[Dan Baker[:dbaker]]

I'm currently debugging this, there might be an issue with the signaling specifically with how ports are being signaled and bundling.

Comment 5

[Dan Baker[:dbaker]]

For Telegram when using the website they have the option to choose an A version or K version. For the A version if we change the check here to check if the msection is disabled in the answer instead of port == 0 the call and media works. For the K version of the app there are different ICE issues I am still debugging.

Comment 6

[Dan Baker[:dbaker]]

For the K version of the app a big problem with calls being placed from Firefox is their app does some SDP parsing. An issue with this is when they perform the following for extmap https://github.com/morethanwords/tweb/blob/master/src/lib/calls/helpers/parseSignalingData.ts#L43 :

    const rtpExtensions: P2PVideoCodec['rtpExtensions'] = codec.rtpExtensions = [];
    section.attributes.get('extmap').forEach((attribute) => {
      rtpExtensions.push({
        id: +attribute.key,
        uri: attribute.value
      });
    });

The issue is with id: +attribute.key which works on an extmap with no directionality specified such as a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level it will properly convert the id to be 1. However if directionality is present such as you would see in Firefox 2/recvonly urn:ietf:params:rtp-hdrext:csrc-audio-level you end up with null for the id and send and SDP with a=extmap:null urn:ietf:params:rtp-hdrext:csrc-audio-level. This causes a parsing error in other browsers and the telegram app preventing the call from working.

Doing something like id: +attribute.key.split('/', 1)[0], instead would resolve this issue on their end.

Comment 7

[Jeff Muizelaar [:jrmuizel]]

Dan, what's next here?

Comment 8

[Calin Tanase]

Attachment: FF Nightly (v138).png

This is still an issue on the latest Nightly.

Comment 9

[Dan Baker[:dbaker]]

The site is not allowing for the calling option for Firefox. In order to test you need to override your UA to mimic Chrome or Safari. A site intervention that spoofed the Chrome UA may work if that's something that can be done.

Calls into Firefox should work from the site. However per comment 6 there are changes the app needs to make in how it parses SDP to make calls from Firefox work, as their current implementation causes them to munge an invalid SDP that ends up being rejected. Maybe this can be solved by a site intervention.

It would be best if we could make contact with the app developers for assistance in resolving these two main blockers and providing us with additional information on issues that we may need to resolve on our end.

Comment 10

[Jeff Muizelaar [:jrmuizel]]

From https://www.linkedin.com/company/telegram-messenger/people/: "Telegram has a "No LinkedIn" policy. Accounts claiming to be past or present employees never worked at Telegram."

That helps explain why we haven't been able to make contact with them so far and why making contact is probably going to be hard.

Dan, is it possible to make our SDP look more like Chrome and Safari's to avoid the parsing problem?

Comment 11

[Dan Baker[:dbaker]]

(In reply to Jeff Muizelaar [:jrmuizel] from comment #10)

From https://www.linkedin.com/company/telegram-messenger/people/: "Telegram has a "No LinkedIn" policy. Accounts claiming to be past or present employees never worked at Telegram."

That helps explain why we haven't been able to make contact with them so far and why making contact is probably going to be hard.

Dan, is it possible to make our SDP look more like Chrome and Safari's to avoid the parsing problem?

We aren't doing anything wrong we are specifying that we only wish to receive a specific header extension and we are doing so according to spec. I don't know our reasoning behind this or who to ask if we are able to switch from receive only to send and receive on that header extension.

Comment 12

[Raul Bucata]

The option is still missing on the latest Nightly

Comment 13

[Andreas Pehrson [:pehrsons] (PTO; back in Aug)]

(In reply to Dan Baker[:dbaker] from comment #11)

I don't know our reasoning behind this or who to ask if we are able to switch from receive only to send and receive on that header extension.

Let's ask nico as author of bug 1439076.

We could also just send them a PR and see what happens.

Comment 14

[Jim Mathies [:jimm]]

So The A version should work fine with the changes that landed in the parent, and with a user agent spoof.

The K version would require changes to our spec handling, which historically has caused all sort of issues (see Google Voice changes for an example). That said we can look at modifying this (NI to Nico on that.) What we can also do here is submit a PR for changes to their code base, which is hosted on Github.

Comment 15

[Jim Mathies [:jimm]]

NI to Dan for the PR.

Comment 16

[Raul Bucata]

The issue is still reproducible

Tested with:

Browser / Version: Firefox Nightly 141.0a1 (2016095847-🦎141.0a1-20250609095449🦎)
Operating System: Google Pixel 3 (Android 12) -1080 x 2160 pixels, 18:9 ratio (~443 ppi density)
Operating System: Oppo Find X5 (Android 13) - 1080 x 2400 pixels, 20:9 ratio (~402 ppi density)

Comment 17

[Raul Bucata]

The issue is still reproducible using the latest Nightly.

Comment 18

[Raul Bucata]

The issue is still reproducible using the latest Nightly.

Comment 19

[Dan Baker[:dbaker]]

• Does this break if you change the UA on the browser to match Chrome? (I don't believe any changes have been made by telegram to present the calling option to Firefox.)
  • Is it broken for inbound and outbound calls?
    • For all versions of the telegram app (A, K, etc.)?

Comment 20

[Raul Bucata]

1. If I spoof as Chrome, everything works ok.
2. • K version does not have the options at all
   • A version has the same outcome as Chrome, or when spoofing as Chrome. (as observed in comment 14 - options are available and working

Comment 21

[BugBot [:suhaib / :marco/ :calixte]]

Since nightly and release are affected, beta will likely be affected too.
For more information, please visit BugBot documentation.

Comment 22

[Raul Bucata]

As noted in previous comments, this issue remains reproducible.

Comment 23

[Raul Bucata]

The issue is still reproducible using the latest Nightly.

Comment 24

[Jeff Muizelaar [:jrmuizel]]

Let's do a nightly only intervention for this for a while and see how it goes.

Comment 25

[Thomas Wisniewski [:twisniewski]]

Attachment: Bug 1903659 - add a UA override for web.telegram.org/a; r?ksenia

Comment 26

[Denis Lisov]

I'm currently on Nightly 2025-11-25 (desktop) and for me https://web.telegram.org/a/ does show the "start call" button in one to one chats without any user agent overrides (or at least without any extensions intended for that). Is this expected or does it mean the problem might have been fixed on Telegram side?

Comment 27

[Thomas Wisniewski [:twisniewski]]

Thanks for the report, Denis. I'll skip shipping an intervention here for now. Dan, do you know the current status of both versions here?

Comment 28

[Dan Baker[:dbaker]]

I have no new information on this issue at this time. Did the call work or just that we see the option to start call now?

Comment 29

[Calin Tanase]

This is still an issue on the latest Nightly (v148) on Android.

Comment 30

[BugBot [:suhaib / :marco/ :calixte]]

There is an r+ patch which didn't land and no activity in this bug for 2 weeks.
:twisniewski, could you have a look please?
If you still have some work to do, you can add an action "Plan Changes" in Phabricator.
For more information, please visit BugBot documentation.

Comment 31

[Thomas Wisniewski [:twisniewski]]

Since Calin was still able to still reproduce, let's ship the intervention on nightly builds and see if that helps.

Comment 32

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/64bd7613fd1d
https://hg.mozilla.org/integration/autoland/rev/80aebd56a8a9
add a UA override for web.telegram.org/a; r=ksenia

Comment 33

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/80aebd56a8a9