testdata: set attribute idprefix to empty

This is to make the generated HTML from asciidoctor match with the
library.
Without it, all IDs are prefixed with "_".

3 files changed, 141 insertions, 140 deletions

diff --git a/testdata/got.test.html b/testdata/got.test.html
index 952f7fa..c0a4ec1 100644
--- a/testdata/got.test.html
+++ b/testdata/got.test.html
@@ -2956,7 +2956,7 @@ this sidebar.</p>
 <div id="footer">
 <div id="footer-text">
  1.1.1<br>
-Last updated 2022-02-21 23:14:09 +0700
+Last updated 2022-07-17 17:00:27 +0700
 </div>
 </div>
 </body>
diff --git a/testdata/test.adoc b/testdata/test.adoc
index ba6b8e9..d8473c5 100644
--- a/testdata/test.adoc
+++ b/testdata/test.adoc
@@ -15,6 +15,7 @@ v1.1.1, 18 July 2020: remark
 :test-url: https://kilabit.info
 :image-sunset: sunset.jpg
 :version-label!:
+:idprefix:
 
 This is preamble.
 :other metadata:
diff --git a/testdata/test.html b/testdata/test.html
index 9d02ab8..ba7dbd6 100644
--- a/testdata/test.html
+++ b/testdata/test.html
@@ -28,115 +28,115 @@
 <div id="toc" class="toc">
 <div id="toctitle">Table of Contents</div>
 <ul class="sectlevel1">
-<li><a href="#_metadata_references">1. Metadata references</a></li>
-<li><a href="#_inline_formatting_on_section">2. <em>Inline <code>formatting</code> on <strong>section</strong></em></a></li>
-<li><a href="#_level_1">3. Level 1</a>
+<li><a href="#metadata_references">1. Metadata references</a></li>
+<li><a href="#inline_formatting_on_section">2. <em>Inline <code>formatting</code> on <strong>section</strong></em></a></li>
+<li><a href="#level_1">3. Level 1</a>
 <ul class="sectlevel2">
-<li><a href="#_level_2">3.1. Level 2</a>
+<li><a href="#level_2">3.1. Level 2</a>
 <ul class="sectlevel3">
-<li><a href="#_level_3">3.1.1. Level 3</a></li>
+<li><a href="#level_3">3.1.1. Level 3</a></li>
 </ul>
 </li>
 </ul>
 </li>
-<li><a href="#_section_two">Section Two</a></li>
-<li><a href="#_section_three">4. Section Three</a></li>
-<li><a href="#_comment">5. Comment</a></li>
-<li><a href="#_paragraph">6. Paragraph</a>
+<li><a href="#section_two">Section Two</a></li>
+<li><a href="#section_three">4. Section Three</a></li>
+<li><a href="#comment">5. Comment</a></li>
+<li><a href="#paragraph">6. Paragraph</a>
 <ul class="sectlevel2">
-<li><a href="#_alignment">6.1. Alignment</a></li>
-<li><a href="#_line_break">6.2. Line break</a></li>
+<li><a href="#alignment">6.1. Alignment</a></li>
+<li><a href="#line_break">6.2. Line break</a></li>
 </ul>
 </li>
-<li><a href="#_unconstrained_text_formatting">7. Unconstrained text formatting</a></li>
-<li><a href="#_single_quote">8. Single quote</a></li>
-<li><a href="#_subscript_and_superscript">9. Subscript and superscript</a></li>
-<li><a href="#_constrained_text_formatting">10. Constrained text formatting</a></li>
-<li><a href="#_blocks">11. Blocks</a>
+<li><a href="#unconstrained_text_formatting">7. Unconstrained text formatting</a></li>
+<li><a href="#single_quote">8. Single quote</a></li>
+<li><a href="#subscript_and_superscript">9. Subscript and superscript</a></li>
+<li><a href="#constrained_text_formatting">10. Constrained text formatting</a></li>
+<li><a href="#blocks">11. Blocks</a>
 <ul class="sectlevel2">
-<li><a href="#_title">11.1. Title</a></li>
+<li><a href="#title">11.1. Title</a></li>
 </ul>
 </li>
-<li><a href="#_block_listing">12. Block listing</a></li>
-<li><a href="#_block_literal">13. Block literal</a></li>
-<li><a href="#_ordered_lists">14. Ordered Lists</a></li>
-<li><a href="#_unordered_lists">15. Unordered Lists</a>
+<li><a href="#block_listing">12. Block listing</a></li>
+<li><a href="#block_literal">13. Block literal</a></li>
+<li><a href="#ordered_lists">14. Ordered Lists</a></li>
+<li><a href="#unordered_lists">15. Unordered Lists</a>
 <ul class="sectlevel2">
-<li><a href="#_custom_markers">15.1. Custom markers</a></li>
-<li><a href="#_checklist">15.2. Checklist</a></li>
+<li><a href="#custom_markers">15.1. Custom markers</a></li>
+<li><a href="#checklist">15.2. Checklist</a></li>
 </ul>
 </li>
-<li><a href="#_mixed_list">16. Mixed list</a></li>
-<li><a href="#_description_list">17. Description list</a></li>
-<li><a href="#_question_and_answers">18. Question and Answers</a></li>
-<li><a href="#_table">19. Table</a>
+<li><a href="#mixed_list">16. Mixed list</a></li>
+<li><a href="#description_list">17. Description list</a></li>
+<li><a href="#question_and_answers">18. Question and Answers</a></li>
+<li><a href="#table">19. Table</a>
 <ul class="sectlevel2">
-<li><a href="#_column_formatting">19.1. Column Formatting</a></li>
-<li><a href="#_cell_formatting">19.2. Cell formatting</a></li>
-<li><a href="#_header_row">19.3. Header row</a></li>
-<li><a href="#_footer_row">19.4. Footer row</a></li>
-<li><a href="#_table_width">19.5. Table width</a></li>
-<li><a href="#_table_borders">19.6. Table borders</a>
+<li><a href="#column_formatting">19.1. Column Formatting</a></li>
+<li><a href="#cell_formatting">19.2. Cell formatting</a></li>
+<li><a href="#header_row">19.3. Header row</a></li>
+<li><a href="#footer_row">19.4. Footer row</a></li>
+<li><a href="#table_width">19.5. Table width</a></li>
+<li><a href="#table_borders">19.6. Table borders</a>
 <ul class="sectlevel3">
-<li><a href="#_frame">19.6.1. Frame</a></li>
-<li><a href="#_grids">19.6.2. Grids</a></li>
+<li><a href="#frame">19.6.1. Frame</a></li>
+<li><a href="#grids">19.6.2. Grids</a></li>
 </ul>
 </li>
-<li><a href="#_striping">19.7. Striping</a></li>
-<li><a href="#_orientation">19.8. Orientation</a></li>
-<li><a href="#_table_caption">19.9. Table caption</a></li>
-<li><a href="#_escaping_the_cell_separator">19.10. Escaping the Cell separator</a></li>
+<li><a href="#striping">19.7. Striping</a></li>
+<li><a href="#orientation">19.8. Orientation</a></li>
+<li><a href="#table_caption">19.9. Table caption</a></li>
+<li><a href="#escaping_the_cell_separator">19.10. Escaping the Cell separator</a></li>
 </ul>
 </li>
-<li><a href="#_horizontal_rules">20. Horizontal rules</a></li>
-<li><a href="#_page_break">21. Page break</a></li>
-<li><a href="#_urls">22. URLs</a></li>
-<li><a href="#_anchors">23. Anchors</a>
+<li><a href="#horizontal_rules">20. Horizontal rules</a></li>
+<li><a href="#page_break">21. Page break</a></li>
+<li><a href="#urls">22. URLs</a></li>
+<li><a href="#anchors">23. Anchors</a>
 <ul class="sectlevel2">
 <li><a href="#version-4_9">23.1. Version 4.9</a></li>
 <li><a href="#version-4_10">23.2. Version 4.10</a></li>
 <li><a href="#which-one">23.3. Version 4.11 </a></li>
 </ul>
 </li>
-<li><a href="#_cross_references">24. Cross references</a>
+<li><a href="#cross_references">24. Cross references</a>
 <ul class="sectlevel2">
-<li><a href="#_internal">24.1. Internal</a></li>
+<li><a href="#internal">24.1. Internal</a></li>
 </ul>
 </li>
-<li><a href="#_include">25. Include</a></li>
-<li><a href="#_images">26. Images</a>
+<li><a href="#include">25. Include</a></li>
+<li><a href="#images">26. Images</a>
 <ul class="sectlevel2">
-<li><a href="#_block_images">26.1. Block images</a></li>
-<li><a href="#_float_group">26.2. Float group</a></li>
-<li><a href="#_inline_image">26.3. Inline image</a></li>
+<li><a href="#block_images">26.1. Block images</a></li>
+<li><a href="#float_group">26.2. Float group</a></li>
+<li><a href="#inline_image">26.3. Inline image</a></li>
 </ul>
 </li>
-<li><a href="#_block_open">27. Block open</a></li>
-<li><a href="#_video">28. Video</a></li>
-<li><a href="#_audio">29. Audio</a></li>
-<li><a href="#_admonition">30. Admonition</a>
+<li><a href="#block_open">27. Block open</a></li>
+<li><a href="#video">28. Video</a></li>
+<li><a href="#audio">29. Audio</a></li>
+<li><a href="#admonition">30. Admonition</a>
 <ul class="sectlevel2">
-<li><a href="#_line_admonition">30.1. Line admonition</a></li>
-<li><a href="#_style_admonition">30.2. Style admonition</a></li>
-<li><a href="#_icons">30.3. Icons</a></li>
+<li><a href="#line_admonition">30.1. Line admonition</a></li>
+<li><a href="#style_admonition">30.2. Style admonition</a></li>
+<li><a href="#icons">30.3. Icons</a></li>
 </ul>
 </li>
-<li><a href="#_sidebar">31. Sidebar</a></li>
-<li><a href="#_example">32. Example</a></li>
-<li><a href="#_quote">33. Quote</a>
+<li><a href="#sidebar">31. Sidebar</a></li>
+<li><a href="#example">32. Example</a></li>
+<li><a href="#quote">33. Quote</a>
 <ul class="sectlevel2">
-<li><a href="#_quoted_paragraph">33.1. Quoted paragraph</a></li>
+<li><a href="#quoted_paragraph">33.1. Quoted paragraph</a></li>
 </ul>
 </li>
-<li><a href="#_verse">34. Verse</a></li>
-<li><a href="#_passthrough">35. Passthrough</a>
+<li><a href="#verse">34. Verse</a></li>
+<li><a href="#passthrough">35. Passthrough</a>
 <ul class="sectlevel2">
-<li><a href="#_block_passthrough">35.1. Block passthrough</a></li>
+<li><a href="#block_passthrough">35.1. Block passthrough</a></li>
 </ul>
 </li>
-<li><a href="#_section_discrete">36. Section Discrete</a>
+<li><a href="#section_discrete">36. Section Discrete</a>
 <ul class="sectlevel2">
-<li><a href="#_after_discrete">36.1. After discrete</a></li>
+<li><a href="#after_discrete">36.1. After discrete</a></li>
 </ul>
 </li>
 </ul>
@@ -170,7 +170,7 @@
 </div>
 </div>
 <div class="sect1">
-<h2 id="_metadata_references"><a class="anchor" href="#_metadata_references"></a><a class="link" href="#_metadata_references">1. Metadata references</a></h2>
+<h2 id="metadata_references"><a class="anchor" href="#metadata_references"></a><a class="link" href="#metadata_references">1. Metadata references</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p>First author: Author A Author {middlename} A <a href="mailto:a@a.com">a@a.com</a>
@@ -190,7 +190,7 @@ AA.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_inline_formatting_on_section"><a class="anchor" href="#_inline_formatting_on_section"></a><a class="link" href="#_inline_formatting_on_section">2. <em>Inline <code>formatting</code> on <strong>section</strong></em></a></h2>
+<h2 id="inline_formatting_on_section"><a class="anchor" href="#inline_formatting_on_section"></a><a class="link" href="#inline_formatting_on_section">2. <em>Inline <code>formatting</code> on <strong>section</strong></em></a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p>Test inline formatting on section title.</p>
@@ -198,16 +198,16 @@ AA.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_level_1"><a class="anchor" href="#_level_1"></a><a class="link" href="#_level_1">3. Level 1</a></h2>
+<h2 id="level_1"><a class="anchor" href="#level_1"></a><a class="link" href="#level_1">3. Level 1</a></h2>
 <div class="sectionbody">
 <div class="sect2">
-<h3 id="_level_2"><a class="anchor" href="#_level_2"></a><a class="link" href="#_level_2">3.1. Level 2</a></h3>
+<h3 id="level_2"><a class="anchor" href="#level_2"></a><a class="link" href="#level_2">3.1. Level 2</a></h3>
 <div class="sect3">
-<h4 id="_level_3"><a class="anchor" href="#_level_3"></a><a class="link" href="#_level_3">3.1.1. Level 3</a></h4>
+<h4 id="level_3"><a class="anchor" href="#level_3"></a><a class="link" href="#level_3">3.1.1. Level 3</a></h4>
 <div class="sect4">
-<h5 id="_level_4"><a class="anchor" href="#_level_4"></a><a class="link" href="#_level_4">Level 4</a></h5>
+<h5 id="level_4"><a class="anchor" href="#level_4"></a><a class="link" href="#level_4">Level 4</a></h5>
 <div class="sect5">
-<h6 id="_level_5"><a class="anchor" href="#_level_5"></a><a class="link" href="#_level_5">Level 5</a></h6>
+<h6 id="level_5"><a class="anchor" href="#level_5"></a><a class="link" href="#level_5">Level 5</a></h6>
 
 </div>
 </div>
@@ -216,19 +216,19 @@ AA.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_section_two"><a class="anchor" href="#_section_two"></a><a class="link" href="#_section_two">Section Two</a></h2>
+<h2 id="section_two"><a class="anchor" href="#section_two"></a><a class="link" href="#section_two">Section Two</a></h2>
 <div class="sectionbody">
 
 </div>
 </div>
 <div class="sect1">
-<h2 id="_section_three"><a class="anchor" href="#_section_three"></a><a class="link" href="#_section_three">4. Section Three</a></h2>
+<h2 id="section_three"><a class="anchor" href="#section_three"></a><a class="link" href="#section_three">4. Section Three</a></h2>
 <div class="sectionbody">
 
 </div>
 </div>
 <div class="sect1">
-<h2 id="_comment"><a class="anchor" href="#_comment"></a><a class="link" href="#_comment">5. Comment</a></h2>
+<h2 id="comment"><a class="anchor" href="#comment"></a><a class="link" href="#comment">5. Comment</a></h2>
 <div class="sectionbody">
 <div class="literalblock">
 <div class="content">
@@ -240,7 +240,7 @@ Indented block comment
 </div>
 </div>
 <div class="sect1">
-<h2 id="_paragraph"><a class="anchor" href="#_paragraph"></a><a class="link" href="#_paragraph">6. Paragraph</a></h2>
+<h2 id="paragraph"><a class="anchor" href="#paragraph"></a><a class="link" href="#paragraph">6. Paragraph</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <div class="title">A Title</div>
@@ -298,7 +298,7 @@ This is next line in paragraph.</p>
 </div>
 </div>
 <div class="sect2">
-<h3 id="_alignment"><a class="anchor" href="#_alignment"></a><a class="link" href="#_alignment">6.1. Alignment</a></h3>
+<h3 id="alignment"><a class="anchor" href="#alignment"></a><a class="link" href="#alignment">6.1. Alignment</a></h3>
 <div class="paragraph text-left">
 <p>This text is left aligned.</p>
 </div>
@@ -313,7 +313,7 @@ This is next line in paragraph.</p>
 </div>
 </div>
 <div class="sect2">
-<h3 id="_line_break"><a class="anchor" href="#_line_break"></a><a class="link" href="#_line_break">6.2. Line break</a></h3>
+<h3 id="line_break"><a class="anchor" href="#line_break"></a><a class="link" href="#line_break">6.2. Line break</a></h3>
 <div class="paragraph">
 <p>Rubies are red,<br>
 Topazes are blue.</p>
@@ -336,7 +336,7 @@ line break</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_unconstrained_text_formatting"><a class="anchor" href="#_unconstrained_text_formatting"></a><a class="link" href="#_unconstrained_text_formatting">7. Unconstrained text formatting</a></h2>
+<h2 id="unconstrained_text_formatting"><a class="anchor" href="#unconstrained_text_formatting"></a><a class="link" href="#unconstrained_text_formatting">7. Unconstrained text formatting</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p><code>__A *B*__</code>: <em>A *B*</em></p>
@@ -371,7 +371,7 @@ line break</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_single_quote"><a class="anchor" href="#_single_quote"></a><a class="link" href="#_single_quote">8. Single quote</a></h2>
+<h2 id="single_quote"><a class="anchor" href="#single_quote"></a><a class="link" href="#single_quote">8. Single quote</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p>'` A single quote without end.</p>
@@ -388,7 +388,7 @@ line break</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_subscript_and_superscript"><a class="anchor" href="#_subscript_and_superscript"></a><a class="link" href="#_subscript_and_superscript">9. Subscript and superscript</a></h2>
+<h2 id="subscript_and_superscript"><a class="anchor" href="#subscript_and_superscript"></a><a class="link" href="#subscript_and_superscript">9. Subscript and superscript</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p>H<sub>2</sub>0 H~ 3 ~0 H~4 ~0 H ~ 5~0 H~6 7~0.</p>
@@ -399,7 +399,7 @@ line break</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_constrained_text_formatting"><a class="anchor" href="#_constrained_text_formatting"></a><a class="link" href="#_constrained_text_formatting">10. Constrained text formatting</a></h2>
+<h2 id="constrained_text_formatting"><a class="anchor" href="#constrained_text_formatting"></a><a class="link" href="#constrained_text_formatting">10. Constrained text formatting</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p><code>_A_B</code>: _A_B</p>
@@ -451,10 +451,10 @@ paragraph*</em>.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_blocks"><a class="anchor" href="#_blocks"></a><a class="link" href="#_blocks">11. Blocks</a></h2>
+<h2 id="blocks"><a class="anchor" href="#blocks"></a><a class="link" href="#blocks">11. Blocks</a></h2>
 <div class="sectionbody">
 <div class="sect2">
-<h3 id="_title"><a class="anchor" href="#_title"></a><a class="link" href="#_title">11.1. Title</a></h3>
+<h3 id="title"><a class="anchor" href="#title"></a><a class="link" href="#title">11.1. Title</a></h3>
 <div class="ulist">
 <div class="title">TODO list</div>
 <ul>
@@ -473,7 +473,7 @@ paragraph*</em>.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_block_listing"><a class="anchor" href="#_block_listing"></a><a class="link" href="#_block_listing">12. Block listing</a></h2>
+<h2 id="block_listing"><a class="anchor" href="#block_listing"></a><a class="link" href="#block_listing">12. Block listing</a></h2>
 <div class="sectionbody">
 <div class="listingblock">
 <div class="content">
@@ -492,7 +492,7 @@ This is not listing.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_block_literal"><a class="anchor" href="#_block_literal"></a><a class="link" href="#_block_literal">13. Block literal</a></h2>
+<h2 id="block_literal"><a class="anchor" href="#block_literal"></a><a class="link" href="#block_literal">13. Block literal</a></h2>
 <div class="sectionbody">
 <div class="literalblock">
 <div class="content">
@@ -517,7 +517,7 @@ A literal named and trailing characters will become paragraph.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_ordered_lists"><a class="anchor" href="#_ordered_lists"></a><a class="link" href="#_ordered_lists">14. Ordered Lists</a></h2>
+<h2 id="ordered_lists"><a class="anchor" href="#ordered_lists"></a><a class="link" href="#ordered_lists">14. Ordered Lists</a></h2>
 <div class="sectionbody">
 <div class="olist arabic">
 <ol class="arabic">
@@ -740,7 +740,7 @@ This line separated by comment.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_unordered_lists"><a class="anchor" href="#_unordered_lists"></a><a class="link" href="#_unordered_lists">15. Unordered Lists</a></h2>
+<h2 id="unordered_lists"><a class="anchor" href="#unordered_lists"></a><a class="link" href="#unordered_lists">15. Unordered Lists</a></h2>
 <div class="sectionbody">
 <div class="ulist">
 <ul>
@@ -961,7 +961,7 @@ This line separated by comment.</p>
 </ul>
 </div>
 <div class="sect2">
-<h3 id="_custom_markers"><a class="anchor" href="#_custom_markers"></a><a class="link" href="#_custom_markers">15.1. Custom markers</a></h3>
+<h3 id="custom_markers"><a class="anchor" href="#custom_markers"></a><a class="link" href="#custom_markers">15.1. Custom markers</a></h3>
 <div class="ulist square">
 <ul class="square">
 <li>
@@ -1034,7 +1034,7 @@ This line separated by comment.</p>
 </div>
 </div>
 <div class="sect2">
-<h3 id="_checklist"><a class="anchor" href="#_checklist"></a><a class="link" href="#_checklist">15.2. Checklist</a></h3>
+<h3 id="checklist"><a class="anchor" href="#checklist"></a><a class="link" href="#checklist">15.2. Checklist</a></h3>
 <div class="ulist checklist">
 <ul class="checklist">
 <li>
@@ -1055,7 +1055,7 @@ This line separated by comment.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_mixed_list"><a class="anchor" href="#_mixed_list"></a><a class="link" href="#_mixed_list">16. Mixed list</a></h2>
+<h2 id="mixed_list"><a class="anchor" href="#mixed_list"></a><a class="link" href="#mixed_list">16. Mixed list</a></h2>
 <div class="sectionbody">
 <div class="olist arabic">
 <ol class="arabic">
@@ -1131,7 +1131,7 @@ This line separated by comment.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_description_list"><a class="anchor" href="#_description_list"></a><a class="link" href="#_description_list">17. Description list</a></h2>
+<h2 id="description_list"><a class="anchor" href="#description_list"></a><a class="link" href="#description_list">17. Description list</a></h2>
 <div class="sectionbody">
 <!-- toc disabled -->
 <div class="dlist">
@@ -1459,7 +1459,7 @@ Hard drive
 </div>
 </div>
 <div class="sect1">
-<h2 id="_question_and_answers"><a class="anchor" href="#_question_and_answers"></a><a class="link" href="#_question_and_answers">18. Question and Answers</a></h2>
+<h2 id="question_and_answers"><a class="anchor" href="#question_and_answers"></a><a class="link" href="#question_and_answers">18. Question and Answers</a></h2>
 <div class="sectionbody">
 <div class="qlist qanda">
 <ol>
@@ -1479,7 +1479,7 @@ Hard drive
 </div>
 </div>
 <div class="sect1">
-<h2 id="_table"><a class="anchor" href="#_table"></a><a class="link" href="#_table">19. Table</a></h2>
+<h2 id="table"><a class="anchor" href="#table"></a><a class="link" href="#table">19. Table</a></h2>
 <div class="sectionbody">
 <table class="tableblock frame-all grid-all stretch">
 <colgroup>
@@ -1545,7 +1545,7 @@ D</p></td>
 </tbody>
 </table>
 <div class="sect2">
-<h3 id="_column_formatting"><a class="anchor" href="#_column_formatting"></a><a class="link" href="#_column_formatting">19.1. Column Formatting</a></h3>
+<h3 id="column_formatting"><a class="anchor" href="#column_formatting"></a><a class="link" href="#column_formatting">19.1. Column Formatting</a></h3>
 <table class="tableblock frame-all grid-all stretch">
 <colgroup>
 <col style="width: 33.3333%;">
@@ -1630,7 +1630,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_cell_formatting"><a class="anchor" href="#_cell_formatting"></a><a class="link" href="#_cell_formatting">19.2. Cell formatting</a></h3>
+<h3 id="cell_formatting"><a class="anchor" href="#cell_formatting"></a><a class="link" href="#cell_formatting">19.2. Cell formatting</a></h3>
 <div class="paragraph">
 <p>Cell duplicated across three columns,</p>
 </div>
@@ -1685,7 +1685,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_header_row"><a class="anchor" href="#_header_row"></a><a class="link" href="#_header_row">19.3. Header row</a></h3>
+<h3 id="header_row"><a class="anchor" href="#header_row"></a><a class="link" href="#header_row">19.3. Header row</a></h3>
 <table class="tableblock frame-all grid-all stretch">
 <colgroup>
 <col style="width: 50%;">
@@ -1722,7 +1722,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_footer_row"><a class="anchor" href="#_footer_row"></a><a class="link" href="#_footer_row">19.4. Footer row</a></h3>
+<h3 id="footer_row"><a class="anchor" href="#footer_row"></a><a class="link" href="#footer_row">19.4. Footer row</a></h3>
 <table class="tableblock frame-all grid-all stretch">
 <colgroup>
 <col style="width: 50%;">
@@ -1755,7 +1755,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_table_width"><a class="anchor" href="#_table_width"></a><a class="link" href="#_table_width">19.5. Table width</a></h3>
+<h3 id="table_width"><a class="anchor" href="#table_width"></a><a class="link" href="#table_width">19.5. Table width</a></h3>
 <table class="tableblock frame-all grid-all" style="width: 75%;">
 <colgroup>
 <col style="width: 50%;">
@@ -1832,9 +1832,9 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_table_borders"><a class="anchor" href="#_table_borders"></a><a class="link" href="#_table_borders">19.6. Table borders</a></h3>
+<h3 id="table_borders"><a class="anchor" href="#table_borders"></a><a class="link" href="#table_borders">19.6. Table borders</a></h3>
 <div class="sect3">
-<h4 id="_frame"><a class="anchor" href="#_frame"></a><a class="link" href="#_frame">19.6.1. Frame</a></h4>
+<h4 id="frame"><a class="anchor" href="#frame"></a><a class="link" href="#frame">19.6.1. Frame</a></h4>
 <table class="tableblock frame-ends grid-all stretch">
 <colgroup>
 <col style="width: 33.3333%;">
@@ -1900,7 +1900,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect3">
-<h4 id="_grids"><a class="anchor" href="#_grids"></a><a class="link" href="#_grids">19.6.2. Grids</a></h4>
+<h4 id="grids"><a class="anchor" href="#grids"></a><a class="link" href="#grids">19.6.2. Grids</a></h4>
 <table class="tableblock frame-all grid-rows stretch">
 <colgroup>
 <col style="width: 33.3333%;">
@@ -1967,7 +1967,7 @@ D</p></td>
 </div>
 </div>
 <div class="sect2">
-<h3 id="_striping"><a class="anchor" href="#_striping"></a><a class="link" href="#_striping">19.7. Striping</a></h3>
+<h3 id="striping"><a class="anchor" href="#striping"></a><a class="link" href="#striping">19.7. Striping</a></h3>
 <table class="tableblock frame-all grid-all stripes-even stretch">
 <colgroup>
 <col style="width: 33.3333%;">
@@ -2074,7 +2074,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_orientation"><a class="anchor" href="#_orientation"></a><a class="link" href="#_orientation">19.8. Orientation</a></h3>
+<h3 id="orientation"><a class="anchor" href="#orientation"></a><a class="link" href="#orientation">19.8. Orientation</a></h3>
 <table class="tableblock frame-all grid-all stretch">
 <colgroup>
 <col style="width: 50%;">
@@ -2109,7 +2109,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_table_caption"><a class="anchor" href="#_table_caption"></a><a class="link" href="#_table_caption">19.9. Table caption</a></h3>
+<h3 id="table_caption"><a class="anchor" href="#table_caption"></a><a class="link" href="#table_caption">19.9. Table caption</a></h3>
 <table class="tableblock frame-all grid-all stretch">
 <caption class="title">Table 1. A formal table</caption>
 <colgroup>
@@ -2169,7 +2169,7 @@ D</p></td>
 </table>
 </div>
 <div class="sect2">
-<h3 id="_escaping_the_cell_separator"><a class="anchor" href="#_escaping_the_cell_separator"></a><a class="link" href="#_escaping_the_cell_separator">19.10. Escaping the Cell separator</a></h3>
+<h3 id="escaping_the_cell_separator"><a class="anchor" href="#escaping_the_cell_separator"></a><a class="link" href="#escaping_the_cell_separator">19.10. Escaping the Cell separator</a></h3>
 <table class="tableblock frame-all grid-all stretch">
 <colgroup>
 <col style="width: 50%;">
@@ -2198,7 +2198,7 @@ D</p></td>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_horizontal_rules"><a class="anchor" href="#_horizontal_rules"></a><a class="link" href="#_horizontal_rules">20. Horizontal rules</a></h2>
+<h2 id="horizontal_rules"><a class="anchor" href="#horizontal_rules"></a><a class="link" href="#horizontal_rules">20. Horizontal rules</a></h2>
 <div class="sectionbody">
 <hr>
 <div class="paragraph">
@@ -2220,7 +2220,7 @@ D</p></td>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_page_break"><a class="anchor" href="#_page_break"></a><a class="link" href="#_page_break">21. Page break</a></h2>
+<h2 id="page_break"><a class="anchor" href="#page_break"></a><a class="link" href="#page_break">21. Page break</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p>Before page break.</p>
@@ -2232,7 +2232,7 @@ D</p></td>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_urls"><a class="anchor" href="#_urls"></a><a class="link" href="#_urls">22. URLs</a></h2>
+<h2 id="urls"><a class="anchor" href="#urls"></a><a class="link" href="#urls">22. URLs</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p><a href="https://asciidoctor.org" class="bare">https://asciidoctor.org</a>.</p>
@@ -2261,7 +2261,7 @@ D</p></td>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_anchors"><a class="anchor" href="#_anchors"></a><a class="link" href="#_anchors">23. Anchors</a></h2>
+<h2 id="anchors"><a class="anchor" href="#anchors"></a><a class="link" href="#anchors">23. Anchors</a></h2>
 <div class="sectionbody">
 <div id="notice" class="paragraph">
 <p>This paragraph gets a lot of attention.</p>
@@ -2303,18 +2303,18 @@ D</p></td>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_cross_references"><a class="anchor" href="#_cross_references"></a><a class="link" href="#_cross_references">24. Cross references</a></h2>
+<h2 id="cross_references"><a class="anchor" href="#cross_references"></a><a class="link" href="#cross_references">24. Cross references</a></h2>
 <div class="sectionbody">
 <div class="sect2">
-<h3 id="_internal"><a class="anchor" href="#_internal"></a><a class="link" href="#_internal">24.1. Internal</a></h3>
+<h3 id="internal"><a class="anchor" href="#internal"></a><a class="link" href="#internal">24.1. Internal</a></h3>
 <div class="paragraph">
-<p>Cross reference with ID <a href="#_anchors">This is anchor</a>.</p>
+<p>Cross reference with ID <a href="#_anchors">[_anchors]</a>.</p>
 </div>
 <div class="paragraph">
 <p>Cross reference with block title <a href="#Anchors">[Anchors]</a>.</p>
 </div>
 <div class="paragraph">
-<p>Cross reference with reftext <a href="#_anchors">This is anchor</a>.</p>
+<p>Cross reference with reftext <a href="#anchors">This is anchor</a>.</p>
 </div>
 <div class="paragraph">
 <p>Cross reference with custom label <a href="#_anchors">custom anchor label</a>.</p>
@@ -2323,7 +2323,7 @@ D</p></td>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_include"><a class="anchor" href="#_include"></a><a class="link" href="#_include">25. Include</a></h2>
+<h2 id="include"><a class="anchor" href="#include"></a><a class="link" href="#include">25. Include</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p>This is inside the fragment1.adoc.</p>
@@ -2345,10 +2345,10 @@ type anchor struct {
 </div>
 </div>
 <div class="sect1">
-<h2 id="_images"><a class="anchor" href="#_images"></a><a class="link" href="#_images">26. Images</a></h2>
+<h2 id="images"><a class="anchor" href="#images"></a><a class="link" href="#images">26. Images</a></h2>
 <div class="sectionbody">
 <div class="sect2">
-<h3 id="_block_images"><a class="anchor" href="#_block_images"></a><a class="link" href="#_block_images">26.1. Block images</a></h3>
+<h3 id="block_images"><a class="anchor" href="#block_images"></a><a class="link" href="#block_images">26.1. Block images</a></h3>
 <div class="imageblock">
 <div class="content">
 <img src="sunset.jpg" alt="sunset">
@@ -2426,7 +2426,7 @@ This is become paragraph.</p>
 </div>
 </div>
 <div class="sect2">
-<h3 id="_float_group"><a class="anchor" href="#_float_group"></a><a class="link" href="#_float_group">26.2. Float group</a></h3>
+<h3 id="float_group"><a class="anchor" href="#float_group"></a><a class="link" href="#float_group">26.2. Float group</a></h3>
 <div class="openblock float-group">
 <div class="content">
 <div class="imageblock left">
@@ -2448,7 +2448,7 @@ This is become paragraph.</p>
 </div>
 </div>
 <div class="sect2">
-<h3 id="_inline_image"><a class="anchor" href="#_inline_image"></a><a class="link" href="#_inline_image">26.3. Inline image</a></h3>
+<h3 id="inline_image"><a class="anchor" href="#inline_image"></a><a class="link" href="#inline_image">26.3. Inline image</a></h3>
 <div class="paragraph">
 <p><span class="image"><img src="https://upload.wikimedia.org/wikipedia/commons/3/35/Tux.svg" alt="Linux" width="25" height="35"></span></p>
 </div>
@@ -2466,7 +2466,7 @@ You can find Linux everywhere these days!</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_block_open"><a class="anchor" href="#_block_open"></a><a class="link" href="#_block_open">27. Block open</a></h2>
+<h2 id="block_open"><a class="anchor" href="#block_open"></a><a class="link" href="#block_open">27. Block open</a></h2>
 <div class="sectionbody">
 <div class="openblock">
 <div class="title">Section inside</div>
@@ -2479,7 +2479,7 @@ You can find Linux everywhere these days!</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_video"><a class="anchor" href="#_video"></a><a class="link" href="#_video">28. Video</a></h2>
+<h2 id="video"><a class="anchor" href="#video"></a><a class="link" href="#video">28. Video</a></h2>
 <div class="sectionbody">
 <div class="videoblock">
 <div class="title">Video without options</div>
@@ -2526,7 +2526,7 @@ Your browser does not support the video tag.
 </div>
 </div>
 <div class="sect1">
-<h2 id="_audio"><a class="anchor" href="#_audio"></a><a class="link" href="#_audio">29. Audio</a></h2>
+<h2 id="audio"><a class="anchor" href="#audio"></a><a class="link" href="#audio">29. Audio</a></h2>
 <div class="sectionbody">
 <div class="audioblock">
 <div class="content">
@@ -2538,10 +2538,10 @@ Your browser does not support the audio tag.
 </div>
 </div>
 <div class="sect1">
-<h2 id="_admonition"><a class="anchor" href="#_admonition"></a><a class="link" href="#_admonition">30. Admonition</a></h2>
+<h2 id="admonition"><a class="anchor" href="#admonition"></a><a class="link" href="#admonition">30. Admonition</a></h2>
 <div class="sectionbody">
 <div class="sect2">
-<h3 id="_line_admonition"><a class="anchor" href="#_line_admonition"></a><a class="link" href="#_line_admonition">30.1. Line admonition</a></h3>
+<h3 id="line_admonition"><a class="anchor" href="#line_admonition"></a><a class="link" href="#line_admonition">30.1. Line admonition</a></h3>
 <div class="paragraph">
 <p>Admonition between a paragraph.
 WARNING: Wolpertingers are known to nest in server racks.
@@ -2628,7 +2628,7 @@ admonition followed by list
 </div>
 </div>
 <div class="sect2">
-<h3 id="_style_admonition"><a class="anchor" href="#_style_admonition"></a><a class="link" href="#_style_admonition">30.2. Style admonition</a></h3>
+<h3 id="style_admonition"><a class="anchor" href="#style_admonition"></a><a class="link" href="#style_admonition">30.2. Style admonition</a></h3>
 <div class="admonitionblock important">
 <table>
 <tr>
@@ -2712,7 +2712,7 @@ Admonition with paragraph.
 </div>
 </div>
 <div class="sect2">
-<h3 id="_icons"><a class="anchor" href="#_icons"></a><a class="link" href="#_icons">30.3. Icons</a></h3>
+<h3 id="icons"><a class="anchor" href="#icons"></a><a class="link" href="#icons">30.3. Icons</a></h3>
 <div class="admonitionblock warning">
 <table>
 <tr>
@@ -2730,7 +2730,7 @@ Enter at your own risk.
 </div>
 </div>
 <div class="sect1">
-<h2 id="_sidebar"><a class="anchor" href="#_sidebar"></a><a class="link" href="#_sidebar">31. Sidebar</a></h2>
+<h2 id="sidebar"><a class="anchor" href="#sidebar"></a><a class="link" href="#sidebar">31. Sidebar</a></h2>
 <div class="sectionbody">
 <div class="sidebarblock">
 <div class="content">
@@ -2760,7 +2760,7 @@ for producing professional documents like DocBook and LaTeX.</p>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_example"><a class="anchor" href="#_example"></a><a class="link" href="#_example">32. Example</a></h2>
+<h2 id="example"><a class="anchor" href="#example"></a><a class="link" href="#example">32. Example</a></h2>
 <div class="sectionbody">
 <div class="exampleblock">
 <div class="title">Example 1. Sample document</div>
@@ -2785,7 +2785,7 @@ This guide provides...</pre>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_quote"><a class="anchor" href="#_quote"></a><a class="link" href="#_quote">33. Quote</a></h2>
+<h2 id="quote"><a class="anchor" href="#quote"></a><a class="link" href="#quote">33. Quote</a></h2>
 <div class="sectionbody">
 <div class="quoteblock">
 <blockquote>
@@ -2823,7 +2823,7 @@ Everybody remember where we parked.
 </div>
 </div>
 <div class="sect2">
-<h3 id="_quoted_paragraph"><a class="anchor" href="#_quoted_paragraph"></a><a class="link" href="#_quoted_paragraph">33.1. Quoted paragraph</a></h3>
+<h3 id="quoted_paragraph"><a class="anchor" href="#quoted_paragraph"></a><a class="link" href="#quoted_paragraph">33.1. Quoted paragraph</a></h3>
 <div class="quoteblock">
 <blockquote>
 I hold it that a little rebellion now and then is a good thing,
@@ -2884,7 +2884,7 @@ a quote
 </div>
 </div>
 <div class="sect1">
-<h2 id="_verse"><a class="anchor" href="#_verse"></a><a class="link" href="#_verse">34. Verse</a></h2>
+<h2 id="verse"><a class="anchor" href="#verse"></a><a class="link" href="#verse">34. Verse</a></h2>
 <div class="sectionbody">
 <div class="verseblock">
 <pre class="content">The fog comes
@@ -2910,13 +2910,13 @@ and then moves on.</pre>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_passthrough"><a class="anchor" href="#_passthrough"></a><a class="link" href="#_passthrough">35. Passthrough</a></h2>
+<h2 id="passthrough"><a class="anchor" href="#passthrough"></a><a class="link" href="#passthrough">35. Passthrough</a></h2>
 <div class="sectionbody">
 <div class="paragraph">
 <p><code>+__A *B*__</code></p>
 </div>
 <div class="sect2">
-<h3 id="_block_passthrough"><a class="anchor" href="#_block_passthrough"></a><a class="link" href="#_block_passthrough">35.1. Block passthrough</a></h3>
+<h3 id="block_passthrough"><a class="anchor" href="#block_passthrough"></a><a class="link" href="#block_passthrough">35.1. Block passthrough</a></h3>
 <video poster="images/movie-reel.png">
   <source src="videos/writing-zen.webm" type="video/webm">
 </video>
@@ -2924,21 +2924,21 @@ and then moves on.</pre>
 </div>
 </div>
 <div class="sect1">
-<h2 id="_section_discrete"><a class="anchor" href="#_section_discrete"></a><a class="link" href="#_section_discrete">36. Section Discrete</a></h2>
+<h2 id="section_discrete"><a class="anchor" href="#section_discrete"></a><a class="link" href="#section_discrete">36. Section Discrete</a></h2>
 <div class="sectionbody">
-<h3 id="_discrete" class="discrete">Discrete</h3>
+<h3 id="discrete" class="discrete">Discrete</h3>
 <div class="paragraph">
 <p>This is content of discrete section.</p>
 </div>
 <div class="sect2">
-<h3 id="_after_discrete"><a class="anchor" href="#_after_discrete"></a><a class="link" href="#_after_discrete">36.1. After discrete</a></h3>
+<h3 id="after_discrete"><a class="anchor" href="#after_discrete"></a><a class="link" href="#after_discrete">36.1. After discrete</a></h3>
 <div class="sidebarblock">
 <div class="content">
 <div class="paragraph">
 <p>Discrete headings are useful for making headings inside of other blocks, like
 this sidebar.</p>
 </div>
-<h2 id="_discrete_heading" class="discrete">Discrete Heading</h2>
+<h2 id="discrete_heading" class="discrete">Discrete Heading</h2>
 <div class="paragraph">
 <p>Discrete headings can be used where sections are not permitted.</p>
 </div>
@@ -2954,7 +2954,7 @@ this sidebar.</p>
 <div id="footer">
 <div id="footer-text">
  1.1.1<br>
-Last updated 2022-02-21 23:14:08 +0700
+Last updated 2022-07-17 17:00:27 +0700
 </div>
 </div>
 </body>