New export errors with TL19

[Guenter Milde]

On 2019-12-12, Jürgen Spitzmüller wrote:

> As to export/export/latex/languages/supported-languages_pdf4_systemF
> and maybe others, I get an error due to missing glyphs.

Which?
It compiles fine here with FreeSerif Version 0412.2263 from the
"fonts-freefont-otf" package version 20120503-9.

> The following preamble setting helps:

> \AtBeginDocument{
>   \@ifpackageloaded{fontspec}{%
>      \newfontfamily\arabicfont[Script=Arabic]{Amiri}%
>   }{}
> }

Should not be required, the log says_

  Package fontspec Info: Font family 'FreeSerif(1)' created for font 'FreeSerif'
  (fontspec)             with options
  (fontspec)             [Ligatures=TeX,Mapping=tex-text,Script=Arabic].
  ...