But it shouldn't be so, because _record_input_props shouldn't care about authority, just like _record_state_props doesn't care about authority.

It absolutely should care about authority. The variables _auth_state_props and _auth_input_props are the properties that we have ownership over. On the other hand, _record_state_props and _record_input_props are the properties we should record.

We record all state properties all the time, because even if we don't own those properties, we still need a history to rewind to. This is in contrast to inputs, where we don't record anything we don't own, but instead wait for those properties to arrive from the owner. This is why _record_input_props and _auth_input_props have the same content.

So imo the better call would either to remove _record_input_props, or - better yet - use that for recording inputs instead of _auth_input_props as it is now.

Currently, without this PR, there is no way to get the input property entries

You're talking about a private property, so even with this PR there wouldn't be a supported way to get input property entries. You can still grab the property names either way.

(it cannot be used without this anyway)

False, see first half of my comment.

Done in #320

So imo the better call would either to remove _record_input_props, or - better yet - use that for recording inputs instead of _auth_input_props as it is now.
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