Ref T13425. When a change adds or removes a block (vs adding or removing a document, or changing a block), we currently try to render null as cell content in the unified view. Make this check broader to catch both "no opposite document" and "no opposite cell".
- Maniphest Tasks
- T13425: Support diffs between abstract block lists in the UI
- rPd4491ddc225e: Fix an issue with 1up diff block rendering for added or removed blocks