Remove textquotedblplain from preamble

[Dr Eberhard Lisse]

This is not an MWE.

It requires several files not provided and has a ton of
entries in the Preamble.

el

On 2022-01-16 21:34 , tush via lyx-users wrote:
> I want to remove it because I don't have any idea what it add or
> alters in the shape of my output file.  I want to have control over
> what is inserted and what is absent in my project.
> 
> The MWE is attached.
> 
> Thanks a lot!
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