@Kool_Baudrillard does it hit specific workflows or randomly across all of them? and can u export one of the affected workflows as JSON and look at the pinData field — empty {} is normal, anything weird in there points at corruption left over from an upgrade migration.
Since pinData is showing as {} , I’d try to capture the next occurrence rather than guessing from this export alone. If it happens again, could you note the exact node name, whether it appears right after opening an old execution or during a fresh run, and grab any browser console or server log errors around that time? That would make it much easier to tell if this is saved workflow state or the editor UI getting confused.