Before, there was not the test "or $title" nor "or $default-title" and when the title was empty, <h1> tag did not appear. Now, I have empty <h1> tags.
That occurs with all services.
<!-- Template used by services for title rendering -->
<xsl:template name="common-service-body-nonempty-content-title-content">
<!-- The title to use -->
<xsl:param name="title"/>
<!-- The default title to use if title is empty (can also be empty) -->
<xsl:param name="default-title"/>
<xsl:choose>
<xsl:when test="$title != '' or $title">
<xsl:call-template name="common-service-body-nonempty-content-title-rendering">
<xsl:with-param name="title" select="$title"/>
</xsl:call-template>
</xsl:when>
<xsl:when test="$default-title != '' or $default-title">
<xsl:call-template name="common-service-body-nonempty-content-title-rendering">
<xsl:with-param name="title" select="$default-title"/>
</xsl:call-template>
</xsl:when>
<xsl:otherwise>
<xsl:call-template name="common-service-body-nonempty-content-title-empty"/>
</xsl:otherwise>
</xsl:choose>
</xsl:template>