According to the CEO's twitter account [0] they are release better support for dependent PRs this year, track progress of that feature here [1].
The crucial problem with code review on GitHub is that it's 100% dependent on Git to store the history of a PR. This too closely couples what a developer does locally on their machine to the code review process. This in turn means that force pushing drops the history of their "Checks" system, which annotate the PR with CI job an lint/test results. It also means junk commits on PRs make the whole review process more difficult. The app Reviewable [2] works with GitHub and fixes some of these issues if you want to give it a try.
The crucial problem with code review on GitHub is that it's 100% dependent on Git to store the history of a PR. This too closely couples what a developer does locally on their machine to the code review process. This in turn means that force pushing drops the history of their "Checks" system, which annotate the PR with CI job an lint/test results. It also means junk commits on PRs make the whole review process more difficult. The app Reviewable [2] works with GitHub and fixes some of these issues if you want to give it a try.
0 - https://twitter.com/natfriedman/status/1170804894241972224
1 - https://github.com/isaacs/github/issues/959
2 - https://reviewable.io