I wrote a document applying styles when I save one and load.
The LibreOffice broke the loading process with reading error message in content.xml.
<office:automatic-styles>
...
<style:style style:name="T354" style:family="text">
  <style:text-properties
    fo:color="#2b91af" 
    style:font-name="Consolas3"
    fo:font-size="9.5pt"
    fo:language="zxx"
    fo:country="none"
    fo:background-color="transparent"
    loext:char-shading-value="0"
    style:font-size-asian="9.5pt"
    style:language-asian="zxx"
    style:country-asian="none"
    style:font-size-complex="9.5pt"
    style:language-complex="zxx"
    style:country-complex="none"
    fo:background-color="#ffffff" />
</style:style>
...

The xml attribute 'fo:background-color="#ffffff"' has already defined.

The automatic style applied to:
<text:p text:style-name="P164">
  <text:span text:style-name="T354">Double</text:span><text:span text:style-name="T239"> Method(</text:span><text:span text:style-name="T353">Double</text:span><text:span text:style-name="T239"> x, </text:span><text:span text:style-name="T354">Double</text:span><text:span text:style-name="T239"> y)</text:span> {<text:span text:style-name="T239"> ...</text:span> }
</text:p>

The events lead to the error can not be found.