This seems to affect only downstream jobs (downstreams, downstreams of downstreams, etc.).

In correct.png, the "Started by GitHub push by iphydf" text links to https://<my-jenkins-url>/job/libtoxcore-toktok_src/43/pollingLog, which is the correct URL.

In incorrect.png, the "Started by GitHub push by iphydf" text links to https://<my-jenkins-url>/pollingLog, which is incorrect URL and it returns 404. It should link to https://<my-jenkins-url>/job/libtoxcore-toktok_src/43/pollingLog instead, but it doesn't.

Job shown in incorrect.png is a downstream of the job shown in correct.png.