Poll events from ghost users are silently dropped when relaying

[formeo14]

I've been running a WhatsApp <-> Matrix <-> Signal relay setup for quite a while now and ran into what I think is a gap in the current relay handling. Polls sent from WhatsApp make it into Matrix just fine as org.matrix.msc3381.poll.start events, but they never show up on Signal, no error, no notice in the room, nothing. It took me a while to even figure out what was happening. (Signal to Matrix is just a normal text message)

• mautrix-whatsapp bridging WhatsApp into Matrix
• mautrix-signal bridging the same Matrix room to Signal
• Relay mode enabled on both bridges, sharing the same Matrix room
• extev_polls: true enabled

But when I send a poll in WhatsApp in a group that is shared/relayed to Signal. I observe that the poll correctly arrives in Matrix as org.matrix.msc3381.poll.start, but that the poll does not appear on Signal
The poll should show up on, just like regular text messages from the same ghost user do.

The Signal bridge logs show:

DBG Ignoring poll event from relayed user
action="handle matrix event"
event_type=org.matrix.msc3381.poll.start
sender=@whatsapp_lid-XXXXXXX:some.tld

The event is decrypted successfully but then explicitly dropped because the sender is identified as a ghost/relay user rather than a real Matrix user.

---

AI-Assisted Code Lookup

Note: The following section was generated with AI assistance after tracing through the source code.

The drop is in bridgev2/portal.go around line 1163:

// bridgev2/portal.go

if origSender != nil {
    if msgContent == nil {
        log.Debug().Msg("Ignoring poll event from relayed user")
        return EventHandlingResultIgnored.WithMSSError(ErrIgnoringPollFromRelayedUser)
    }
    if !caps.PerMessageProfileRelay {
        msgContent, err = portal.Bridge.Config.Relay.FormatMessage(msgContent, origSender)
        ...
    }
}

Why this triggers for polls specifically:

Earlier in the same handler, the event content is resolved into one of three separate typed variables:

Event type	Variable set
m.room.message / sticker	msgContent ✅
org.matrix.msc3381.poll.start	pollContent
org.matrix.msc3381.poll.response	pollResponseContent

When a poll event arrives, msgContent is nil and only pollContent is populated. The relay path then hits origSender != nil && msgContent == nil which is exactly the condition that fires when a ghost/bridge user sends a poll and immediately returns EventHandlingResultIgnored.

Regular messages work fine because msgContent is not nil for them, so they fall through to the FormatMessage relay formatting step (which prepends the ghost user's display name) and continue to be forwarded.

The error is defined in bridgev2/errors.go:

ErrIgnoringPollFromRelayedUser error = WrapErrorInStatus(
    errors.New("ignoring poll event from relayed user"),
).WithIsCertain(true).WithSendNotice(false)

The WithSendNotice(false) is why there is no visible error message in the Matrix room — the drop is completely silent from a user perspective.

Root cause summary: There is no relay formatting path for poll content types. The relay logic in bridgev2 only knows how to prepend sender info to *event.MessageEventContent. No equivalent exists for *event.PollStartEventContent, so poll events from relayed users are unconditionally dropped rather than forwarded.

---

Feature Request

Please add a configuration option to allow poll events from relayed/ghost users to be forwarded. For example:

network:
    extev_polls: true
    relay_extev_polls: true  # new: allow polls from ghost users to be relayed

Alternatively, treating poll events from ghost users the same way regular messages from ghost users are treated, forwarding them as native Signal polls without relay-prefix formatting.