Blocked and blocking on GitHub boards
GitHub added issue dependencies, and the relationships turned out to be present in responses we were already fetching. So the blocked and blocking indicators built for GitLab boards now work on GitHub boards too — same card indicators, same hover highlighting, same connector lines, same Blocking filter.
Nothing about your board configuration needs to change.
One honest note about freshness. A change to a dependency does not always register as a change to the issue itself on GitHub's side, which means it will not necessarily arrive on the next incremental sweep the way an edit to a title would. It settles on the fuller reconciliation that runs underneath. If a dependency you have just set is not showing yet, that is why, and Sync now will fetch it.