<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">After an interval of around 2 months, I am again processing a book-length memoir-class document under an up-to-date MacTeX/TeXLive 2020. The document uses biblatex and babel. Even though nowhere do I use basque, nonetheless I am getting now a totally unexpected error:<div class=""><pre class="lang-tex s-code-block latex hljs" style="margin: 0px 0px calc(var(--s-prose-spacing) + 0.4em); padding: 12px; border: 0px; font-stretch: inherit; line-height: 1.30769231; font-size: 13px; vertical-align: baseline; box-sizing: inherit; width: auto; max-height: 600px; overflow: auto; border-top-left-radius: 5px; border-top-right-radius: 5px; border-bottom-right-radius: 5px; border-bottom-left-radius: 5px; color: var(--highlight-color); word-wrap: normal;"><code style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: 19.5px; vertical-align: baseline; box-sizing: inherit; white-space: inherit;" class=""><font face="Courier" class="">Package biblatex Info: Trying to load language 'english' -> 'mylanguagestrings'
...
Package biblatex Info: ... file 'mylanguagestrings.lbx' found.
(/Users/murray/Library/texmf/tex/latex/biblatex/lbx/mylanguagestrings.lbx
File: mylanguagestrings.lbx
Package biblatex Info: Trying to load language 'english'...
Package biblatex Info: ... file 'english.lbx' found.
(/usr/local/texlive/2020/texmf-dist/tex/latex/biblatex/lbx/english.lbx
File: english.lbx 2020/08/23 v3.15a biblatex localization (PK/MW)
)
Package biblatex Info: Trying to load language 'english'...
Package biblatex Info: ... file 'english.lbx' found.
(/usr/local/texlive/2020/texmf-dist/tex/latex/biblatex/lbx/english.lbx
File: english.lbx 2020/08/23 v3.15a biblatex localization (PK/MW)
/usr/local/texlive/2020/texmf-dist/tex/latex/biblatex/lbx/english.lbx:571: Pack
age xkeyval Error: `langbasque' undefined in families `blx@lbx'.</font></code></pre><div class="">In the source directory I have a <font face="Courier" class="">biblatex.cfg </font>that includes the line:</div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><font face="Courier" size="2" class="">\DeclareLanguageMapping{english}{mylanguagestrings} % external file!</font></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><font face="Courier" size="2" class=""><br class=""></font></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">And in<font face="Courier" class=""> /Library/texmf/tex/latex/biblatex/lbx</font> I have the referenced file mylanguagestrings.lbx which includes the following:</div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><br class=""></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><font face="Courier" class="">\InheritBibliographyExtras{english}</font></div><div style="margin: 0px; font-stretch: normal; font-size: 18px; line-height: normal;" class=""><br class=""></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">Unfortunately, I am unable to reproduce the error so far in a small document, just in the book-length document with its several long files input in the preamble.</div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class=""><br class=""></div><div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">Any suggestion on trouble-shooting this would be welcome!</div></div><div class="">
<div style="color: rgb(0, 0, 0); letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">---<br class="">Murray Eisenberg<span class="Apple-tab-span" style="white-space: pre;"> </span><a href="mailto:murrayeisenberg@gmail.com" class="">murrayeisenberg@gmail.com</a><br class="">503 King Farm Blvd #101<span class="Apple-tab-span" style="white-space: pre;"> </span><br class="">Rockville, MD 20850-6667<span class="Apple-tab-span" style="white-space: pre;"> </span>Mobile (413)-427-5334<br class=""><br class=""></div>
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