Publii 0.36 Prerelease 4!
Thank you for your message, I really appreciate any comments that help us improve our products. The block editor is our brand new project and it will take some time before we refine it to perfection.
In response to your theme upgrade question: we change nothing in this matter, however, support for all Block Editor options will require the addition of a small piece of new CSS rules. At the right time I will indicate where and what changes should be applied.
Do you appreciate the support you've received today? If so, consider donating to the Publii team by clicking here; we'll be sure to use your donation to make Publii even better!