Verified session is shown as 'Not trusted'

[matrixbot]

This issue was originally created by @dimonb at matrix-org/dendrite#3412.

Background information

• Dendrite version or git SHA: /etc/dendrite # 0.13.7+14a6c10
• SQLite3 or Postgres?: postgres
• Running in Docker?: yes
• go version:
• Client used (if applicable): Any client

Description

• What is the problem:
  Some verified sessions shown as 'Not Trusted' to others if contact verified after session
• Who is affected:
  Any who verify my contact after I've added new session
• How is this bug manifesting:
  Your contact shown as not trusted to others when then verify you
• When did this first appear:
  When I register new session with other device after contact verification

session AG3_a329 is Verified. Marked as green and all seems nice.

session AG3_a329 shown as not trusted

Refreshing clients does not help. Problem is reproduces on app.element.io

Steps to reproduce

• create test account on homeserver
• create test account on matrix.org
• verify each other
• register new session in homesever
• session of test user shown as 'Not trusted' on matrix.org

[matrixbot]

This comment was originally posted by @Kimiblock at matrix-org/dendrite#3412 (comment).

I recently saw this happening. The solution is to force a device list refresh on Synapse:

INSERT INTO device_lists_remote_resync                   
VALUES ('@mxid:example.org', (EXTRACT(epoch FROM NOW()) * 1000)::BIGINT);