TOPIC: Pancake breakers

A panel I inspected this morning had several pancake breakers, of differing brands.  The sticker on the panel indicates that this panel cannot accept this type of breaker.  Am I reading it correctly, or is it OK.  Thank you.

You cut off the part that says only use one brand breaker but I see part of it at the bottom right.
Pancake breakers ?
Never heard that term but guessing you mean (tandem)mini breakers.
Mini breakers are fine but as in Chicago some localities may not allow them by code.

They are normally used because the panel is full and can not accept any more and they help avoid needing a sub or another larger panel.
The issue for some may be that adding more circuits can perhaps overload the panel capacity however we do not do load calculations as part of a Home Inspection.

Jeez Bob... you're not "waffle-ing" on your reply now, are ya?  ;D

According to the number 20-20, this would mean there are 20 slots, and only up to 20 breakers could be used, meaning none of the spots are suitable for tandem breakers.  Am I reading that correctly.  I understand why they use tandem breakers, just not sure if this box allows them.