For example, if a Ledger file contains transactions with the use of both
EUR and EUR {=PRICE}, then regular reports will always show the
{=PRICE}, disabling the by-name commodity merging that takes place. In
brief, fixated and non-fixated commodities are now non-mergable.
If a file contains all of one, or all of the other, they will still be
merged, since these separate usages do not conflict the way that fixated
and non-fixated together do.
