Upgrade Status module is generating warnings that Read-only properties are incompatible with DependencySerializationTrait. This affects both the settings form and the block generated by this module.
Research led me to Dependency Injection in a form, which says "be sure to not set any service properties in your form class to have private visibility." I would assume the same warning applies to blocks for similar reasons.
Comments
Comment #3
micahw156Fixed.
Comment #5
micahw156Update status is still throwing warnings on this issue, so the change might not have been necessary.