Preview in converter doesn't match the result after a Preview-Button click

[LyricsLover]

Please have a look at this converter Tag-Tag Format string for _FILENAME:
$if($grtr($len(%_total_files%),1),$num(%track%,$len(%_total_files%)) - $validate(%title%)),$num(%track%,2) - $validate(%title%))

The TITLE content looks like this (note the different case spelling)

If you press the Preview-Button you get:

D:\L\Laura Wilde\Unbeschreiblich\2021\09 - Momente Wie Diese.mp3
  "" ->
  "Invalid IF syntax"

Should we not see the immediate preview (above the Preview-Button) with the same
"Invalid IF syntax"?

[Florian]

I'll look into this, thanks for pointing!

[Florian]

Syntax errors in the format string are now displayed in the live preview with Mp3tag v3.14a.

[LyricsLover]

Thanks, now it works as expected in the live preview too!

For those interested: This is the working format string:
$ifgreater($len(%_total_files%),1,$num(%track%,$len(%_total_files%)) - $validate(%title%,),$num(%track%,2) - $validate(%title%,))