Timestamps have disappeared from read receipts

[turt2live]

No description provided.

[turt2live]

Only sometimes though?

Dave is reliably reproducible as someone without a timestamp, however other people do have timestamps.

Not culprits:

• matrix.org
• avatar vs no avatar
• message type (notice, text, etc all have the same behaviour)
• room (happens in all tested rooms)

[turt2live]

also they aren't ordered correctly anymore:

(Middle is Delph, who does not have a timestamp)

Edit: Until richvdh came by, at least:

[turt2live]

Finally actually got a chance to look at this, and it actually appears to be a matrix.org issue. The read receipts not having issues are synthesized, and aren't affected.

Something with matrix.org is definitely not doing the right thing though. Here's the raw read receipt:

            {
              "type": "m.receipt",
              "content": {
                "$1553059866145EthFl:dev.t2host.io": {
                  "m.read": {
                    "@turt2live:matrix.org": "{\"ts\": 1553059870117}"
                  }
                }
              }
            }

[turt2live]

Closing in favour of synapse issue: matrix-org/synapse#4898