SUMMARY
While looking more at bug 406243 I found some oddness in share operations. They 

STEPS TO REPRODUCE
The QIF file contains 
^
!Account
NMyBrokerage 666
TInvst
^
!Type:Invst
D12/22'10
NCash
L[MyBrokerage 666]
^
D12/23'10
NShrsIn
Y 
Q31
Cc
MISHARES TRUST S&P 500   S&P 500 INDEX
^


OBSERVED RESULT

The ISHARES operation in [Shares] view appears as
Account: MyBrokerage 666
Amount: +31.00 $
Payee, Mode, Number: <blank>
Comment: ISHARES TRUST S&P 500   S&P 500 INDEX (the 'M' field)
Account for payment: <the first account in the drop-down, the default?>
Amount of shares: <blank>
Commission, Tax: <blank>

EXPECTED RESULT
The '$' for amount should be the investment symbol (available in the drop-down).
Maybe the amounts shouldn't have two decimal points when it's a Quantity of shares, though for other kinds of funds I think there can be decimal fractions of a share.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.14.5
KDE Frameworks Version: 5.55.0
Qt Version: 5.11.3

ADDITIONAL INFORMATION
I also noticed other glitches with shares, but I don't have time to track them down:
* NShrsOut transactions also appear as amount increases, I think they should be decreases (red).
* An NShrsOut transactions that is "MXfr To: AnotherAccount 999" doesn't seem to show up as a transfer.
* NDiv dividend transactions aren't marked as anything special, that seems useful; for other kinds of transactions the 'N' shows up as a category.