We’ve been there before, but it is a very big problem when opening GH definitions and find “holes” in the definition due to missing - or the actual problem - unknown missing components, when a plugin is missing or a component is no longer compatible.
Since there is some info about the components in the .gh/.ghx file, a placeholder should be put in place, even a panel with all available info dumped into it, or a dummy component with the connections preserved. One idea for this would be to attach a C# ScriptComponent and autogenerate Params and connect them, + inject a silly error message yelling at the world about its soul being lost.
Or something. Whatever we can or cannot, we cannot have “holes” in the definitions. Especially bad now when in a transition period going from R5 to R6. Mistakes are made way too easy. If saving such a file then… its broken and irrecoverable definitions lost (especially if its a def by someone else and you don’t have a clue what was there, or how)
A placeholder should be introduced asap. Critical.