A bridgehead is formatted as a block, using the same display properties as the section heading which it masquerades as. The renderas attribute controls which heading it mimics.

Bridge heads are not numbered, even when they are rendered as headings that are otherwise numbered.

Common attributes and common linking attributes.

any attribute

Any attribute in any other explicit namespace

otherrenderas

Identifies the nature of the non-standard rendering

renderas

Indicates how the bridge head should be rendered

Enumerated values:
“sect1”	Render as a first-level section
“sect2”	Render as a second-level section
“sect3”	Render as a third-level section
“sect4”	Render as a fourth-level section
“sect5”	Render as a fifth-level section

These elements contain bridgehead: abstract, acknowledgements, annotation, answer, appendix, article, bibliodiv, bibliography, bibliolist, blockquote, callout, calloutlist, caption (db.caption), caution, chapter, colophon, constraintdef, cover, danger, dedication, entry, example, figure, footnote, glossary, glossdef, glossdiv, glosslist, important, index, indexdiv, informalexample, informalfigure, itemizedlist, legalnotice, listitem, meta (db.meta.content), msgexplan, msgtext, note, orderedlist, para, partintro, preface, procedure, qandadiv, qandaset, question, refsect1, refsect2, refsect3, refsection, refsynopsisdiv, result, revdescription, sect1, sect2, sect3, sect4, sect5, section, setindex, sidebar, simplesect, step, taskprerequisites, taskrelated, tasksummary, td, textobject, th, tip, toc, tocdiv, topic, variablelist, warning.

The following elements occur in bridgehead: text, abbrev, accel, acronym, alt, anchor, annotation, application, author, biblioref, buildtarget, citation, citebiblioid, citerefentry, citetitle, classname, code, command, computeroutput, constant, coref, database, date, editor, email, emphasis (db._emphasis), emphasis (db.emphasis), enumidentifier, enumname, enumvalue, envar, errorcode, errorname, errortext, errortype, exceptionname, filename, firstterm (db._firstterm), firstterm (db.firstterm), footnote, footnoteref, foreignphrase (db._foreignphrase), foreignphrase (db.foreignphrase), function, glossterm (db._glossterm), glossterm (db.glossterm), guibutton, guiicon, guilabel, guimenu, guimenuitem, guisubmenu, hardware, indexterm (db.indexterm.endofrange), indexterm (db.indexterm.singular), indexterm (db.indexterm.startofrange), initializer, inlineequation, inlinemediaobject, interfacename, jobtitle, keycap, keycode, keycombo, keysym, link, literal, macroname, markup, menuchoice, methodname, modifier, mousebutton, nonterminal, olink, ooclass, ooexception, oointerface, option, optional, org, orgname, package, parameter, person, personname, phrase (db._phrase), phrase (db.phrase), productname, productnumber, prompt, property, quote (db._quote), quote (db.quote), remark, replaceable, returnvalue, revnumber, shortcut, subscript, superscript, symbol, systemitem, tag, templatename, termdef, token, trademark, type, typedefname, unionname, uri, userinput, varname, wordasword, xref.