$replace()/$regex() breaks with %_total_size% (in export)

#1
Export code example 1: 
%_total_size% => $replace(z0z %_total_size% z0z,0,X)

Result:

104,27 MB => z0z 104

Expected:

104,27 MB => zXz 1X4,27 MB zXz

Problem:
No replacement at all and things after %_total_size% are not even included.

Export code example 2: 
%_total_size% => $replace(z0z $trim(%_total_size%) z0z,0,X)

Result:

104,27 MB => zXz 1X4 zXz

Expected:

104,27 MB => zXz 1X4,27 MB zXz

Problem:
%_total_size% does not have any unit nor decimal part.

Same behavior can be observed with $regex(), and I'm guessing other (string) functions. Is this bug by design?

Frage zum globale Platzhalter %_total_size%
Changing format/locale of %_total_size% (in export)
#2

Yes this looks like a bug.
I was able to repeat the buggy behaviour.
20110812.Test.mte (662 Bytes)

But I am not really sure, because Mp3tag system info fields are not tag fields, and it is not documented, if info fields can be treated the same way as tag fields in the Mp3tag export environment.

DD.20110812.0422.CEST

20110812.Test.mte (662 Bytes)