Option: Custom Attributes String

The extension option Custom attributes string on the extension configuration dialog box, is a space-separated list of attribute settings that the Asciidoctor Browser Extension applies to all documents when rendering them to HTML.

The Custom attributes string option allows you to use the features of AsciiDoc in documents without having to write them each time, or include a separate file of attribute settings.

For example, to use the GUI macros for every AsciiDoc you preview with the extension, you can set experimental in the Custom attributes string.


You can also use URL query parameters to set attributes.

Setting attribute values

Attributes can be set with and without a value, and unset. The following table shows examples of setting attributes in AsciiDoc with their Custom Attribute equivalents.

Action In AsciiDoc In custom attributes

Set without a value





Set to a value

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Setting an attribute in the string is not a guarantee that it will take effect, as it may be incompatible with the browser view, or be overruled by another setting of that option. See section Set AsciiDoc attributes on the features page.

Use cases

For more ideas and use cases for setting attributes, see the Use Cases page.

AsciiDoc attributes

To learn more about AsciiDoc attributes, visit the Document Attributes page of the AsciiDoc manual.