[GNC] Missing 2nd entry

[Fred Tydeman]

I just found a transaction that is not a double entry.
It is just a single entry.  Not sure how that happened.
When I click on Split to see the other side of the entry,
there is nothing.  Clicking on Jump does nothing.

With that strange transaction as the current entry:
Clicking on Actions->Check&Repair->This transaction
appears to do nothing.  Same for All transactions.

With all account tabs closed (so only the top level Accounts shows):
Clicking on Actions->Check&Repair->Check&repair all
runs for a minute or two and does not fix that entry, nor
make a new account for Unbalanced or similar.

I wonder if this unusual transaction is the cause of the
Trial Balance report crashing and giving me a traceback.
Equity Statement report also crashes with a similar traceback.

I am running GnuCash 4.10+(2022-03-26) on Linux.