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<?xml version="1.0" standalone="no"?>
<!DOCTYPE document PUBLIC "-//APACHE//DTD Documentation V1.1//EN"
    "http://cvs.apache.org/viewcvs.cgi/*checkout*/xml-forrest/src/core/context/resources/schema/dtd/document-v12.dtd">

<document>
  <header>
    <title>User agent refs</title>
    <authors>
      <person name="Peter B. West" email="pbwest@powerup.com.au"/>
    </authors>
  </header>
  <body>
    <section>
      <title>User Agent references in XSLFO</title>
      <section>
        <title>4.9.2 Viewport Geometry</title>
        <p>
          If the block-progression-dimension of the reference-area is
          larger than that of the viewport-area and the overflow trait
          for the reference-area is scroll, then the
          inline-scroll-amount and block-scroll-amount are determined
          by a scrolling mechanism, if any, provided by the
          <strong>user agent</strong>. Otherwise, both are zero.
        </p>
      </section>
      <section>
        <title>5.1.3 Actual Values</title>
        <p>
          A computed value is in principle ready to be used, but a
          user agent may not be able to make use of the value in a
          given environment. For example, a <strong>user
            agent</strong> may only be able to render borders with
          integer pixel widths and may, therefore, have to adjust the
          computed width to an integral number of media pixels.
        </p>
      </section>
      <section>
        <title>5.5.7 Font Properties</title>
        <p>
          There is no XSL mechanism to specify a particular font;
          instead, a selected font is chosen from the fonts available
          to the <strong>User Agent</strong> based on a set of
          selection criteria. The selection criteria are the following
          font properties: "font-family", "font-style",
          "font-variant", "font-weight", "font-stretch", and
          "font-size", plus, for some formatting objects, one or more
          characters.
        </p>
      </section>
      <section>
        <title>5.9.13.1 Pixels</title>
        <p>
          If the <strong>User Agent</strong> chooses a measurement for
          a 'px' that does not match an integer number of device dots
          in each axis it may produce undesirable effects...
        </p>
      </section>
      <section>
        <title>5.10.4 Property Value Functions</title>
        <section>
          <title>Function: object merge-property-values( NCName)</title>
          <p>
            The merge-property-values function returns a value of the
            property whose name matches the argument, or if omitted
            for the property for which the expression is being
            evaluated. The value returned is the specified value on
            the last fo:multi-property-set, of the parent
            fo:multi-properties, that applies to the <strong>User
              Agent</strong> state. If there is no such value, the
            computed value of the parent fo:multi-properties is
            returned...
          </p>
          <p>
            The test for applicability of a <strong>User
              Agent</strong> state is specified using the "active-state"
            property.
          </p>
        </section>
      </section>
      <section>
        <title>6.3 Formatting Objects Summary</title>
        <section>
          <title>multi-property-set</title>
          <p>
            The fo:multi-property-set is used to specify an
            alternative set of formatting properties that, dependent
            on a <strong>User Agent</strong> state, are applied to the
            content.
          </p>
        </section>
        <section>
          <title>title</title>
          <p>
            The fo:title formatting object is used to associate a
            title with a given page-sequence. This title may be used
            by an interactive <strong>User Agent</strong> to identify
            the pages. For example, the content of the fo:title can be
            formatted and displayed in a "title" window or in a "tool
            tip".
          </p>
        </section>
      </section>
      <section>
        <title>6.4.1.2 Page-masters</title>
        <p>
          ... When pages are used with a <strong>User Agent</strong>
          such as a Web browser, it is common that the each document
          has only one page. The viewport used to view the page
          determines the size of the page. When pages are placed on
          non-interactive media, such as sheets of paper, pages
          correspond to one or more of the surfaces of the paper.
        </p>
      </section>
      <section>
        <title>6.4.20 fo:title</title>
        <section>
          <title>Common Usage:</title>
          <p>
            ... This title may be used by an interactive <strong>User
              Agent</strong> to identify the pages.
          </p>
        </section>
      </section>
      <section>
        <title>6.6.3 fo:character</title>
        <section>
          <title>Constraints:</title>
          <p>
            The dimensions of the areas are determined by the font
            metrics for the glyph.
          </p>
          <p>
            When formatting an fo:character with a
            "treat-as-word-space" value of "true", the <strong>User
              Agent</strong> may use a different method for determining
            the inline-progression-dimension of the area.
          </p>
        </section>
      </section>
      <section>
        <title>6.9 Dynamic Effects: Link and Multi Formatting
          Objects</title>
        <section>
          <title>6.9.1 Introduction</title>
          <p>
            Dynamic effects, whereby user actions (including
            <strong>User Agent</strong> state) can influence the
            behavior and/or representation of portions of a document,
            can be achieved through the use of the formatting objects
            included in this section:
          </p>
          <ul>
            <li>One-directional single-target links.</li>
            <li>
              The ability to switch between the display of two or more
              formatting object subtrees. This can be used for, e.g.,
              expandable/collapsible table of contents, display of an
              icon or a full table or graphic.
            </li>
            <li>
              The ability to switch between different property values,
              such as color or font-weight, depending on a
              <strong>User Agent</strong> state, such as "hover".
            </li>
          </ul>
        </section>
      </section>
      <section>
        <title>6.10 Out-of-Line Formatting Objects</title>
        <section>
          <title>6.10.1.3 Conditional Sub-Regions</title>
          <p>
            ... There may be limits on how much space conditionally
            generated areas can borrow from the
            region-reference-area. It is left to the <strong>user
              agent</strong> to decide these limits.
          </p>
          <p>
            ... An interactive <strong>user agent</strong> may choose
            to create "hot links" to the footnotes from the
            footnote-citation, or create "hot links" to the
            before-floats from an implicit citation, instead of
            realizing conditional sub-regions.
          </p>
        </section>
      </section>
      <section>
        <title>6.10.2 fo:float</title>
        <section>
          <title>Constraints:</title>
          <p>
            ... The <strong>user agent</strong> may make its own
            determination, after taking into account the intrusion
            adjustments caused by one or more overlapping side-floats,
            that the remaining space in the
            inline-progression-direction is insufficient for the next
            side-float or normal block-area. The <strong>user
              agent</strong> may address this by causing the next
            side-float or normal block-area to "clear" one of the
            relevant side-floats, as described in the "clear" property
            description, so the intrusion adjustment is sufficiently
            reduced. Of the side-floats that could be cleared to meet
            this constraint, the side-float that is actually cleared
            must be the one whose after-edge is closest to the
            before-edge of the parent reference-area.
          </p>
          <p>
            The <strong>user agent</strong> may determine sufficiency
            of space by using a fixed length, or by some heuristic
            such as whether an entire word fits into the available
            space, or by some combination, in order to handle text and
            images.
          </p>
        </section>
      </section>
      <section>
        <title>6.10.3 fo:footnote</title>
        <section>
          <title>Constraints:</title>
          <p>
            ... The second block-area and any additional block-areas
            returned by an fo:footnote must be placed on the
            immediately subsequent pages to the page containing the
            first block-area returned by the fo:footnote, before any
            other content is placed. If a subsequent page does not
            contain a region-body, the <strong>user agent</strong>
            must use the region-master of the last page that did
            contain a region-body to hold the additional block-areas.
          </p>
        </section>
      </section>
      <section>
        <title>7.3 Reference Rectangle for Percentage Computations</title>
        <p>...</p>
        <section>
          <title>Exceptions ...</title>
          <p>
            5. When the absolute-position is "fixed", the containing
            block is defined by the nearest ancestor viewport area. If
            there is no ancestor viewport area, the containing block
            is defined by the <strong>user agent</strong>.
          </p>
        </section>
      </section>
      <section>
        <title>7.6.5 "pause-after" 7.6.6 "pause-before" 7.6.17
        "voice-family"</title>
        <p>
          Initial: depends on <strong>user agent</strong>
        </p>
      </section>
      <section>
        <title>7.7.1 "background-attachment"</title>
        <section>
          <title>fixed</title>
          <p>
            ... <strong>User agents</strong> may treat fixed as
            scroll. However, it is recommended they interpret fixed
            correctly, at least for the HTML and BODY elements, since
            there is no way for an author to provide an image only for
            those browsers that support fixed.
          </p>
        </section>
      </section>
      <section>
        <title>7.7.9 "border-before-width"</title>
        <section>
          <title>&lt;length-conditional&gt;</title>
          <p>
            ... If border-before-width is specified using one of the
            width keywords the .conditional component is set to
            "discard" and the .length component to a <strong>User
              Agent</strong> dependent length.
          </p>
        </section>
      </section>
      <section>
        <title>7.7.19 "border-top-color"</title>
        <section>
          <title>&lt;color&gt;</title>
          <p>
            ... If an element's border color is not specified with a
            "border" property, <strong>user agents</strong> must use
            the value of the element's "color" property as the
            computed value for the border color.
          </p>
        </section>
      </section>
      <section>
        <title>7.7.20 "border-top-style"</title>
        <p>
          Conforming HTML <strong>user agents</strong> may interpret
          'dotted', 'dashed', 'double', 'groove', 'ridge', 'inset',
          and 'outset' to be 'solid'.
        </p>
      </section>
      <section>
        <title>7.7.21 "border-top-width"</title>
        <section>
          <title>thin ... medium ... thick ...</title>
          <p>
            ... The interpretation of the first three values depends
            on the <strong>user agent</strong>.
          </p>
        </section>
      </section>
      <section>
        <title>7.8.2 "font-family"</title>
        <p>Initial: depends on <strong>user agent</strong></p>
      </section>
      <section>
        <title>7.8.3 "font-selection-strategy"</title>
        <p>
          There is no XSL mechanism to specify a particular font;
          instead, a selected font is chosen from the fonts available
          to the <strong>User Agent</strong> based on a set of
          selection criteria. The selection criteria are the following
          font properties: "font-family", "font-style",
          "font-variant", "font-weight", "font-stretch", and
          "font-size", plus, for some formatting objects, one or more
          characters.
        </p>
        <p>
          ... This fallback may be to seek a match using a
          <strong>User Agent</strong> default "font-family", or it may
          be a more elaborate fallback strategy where, for example,
          "Helvetica" would be used as a fallback for "Univers".
        </p>
        <p>
          If no match has been found for a particular character, there
          is no selected font and the <strong>User Agent</strong>
          should provide a visual indication that a character is not
          being displayed (for example, using the 'missing character'
          glyph).
        </p>
      </section>
      <section>
        <title>7.8.4 "font-size"</title>
        <section>
          <title>&lt;absolute-size&gt;</title>
          <p>
            An &lt;absolute-size&gt; keyword refers to an entry in a
            table of font sizes computed and kept by the <strong>user
              agent</strong>. Possible values are:<br/>[ xx-small |
            x-small | small | medium | large | x-large | xx-large ]
          </p>
        </section>
        <section>
          <title>&lt;relative-size&gt;</title>
          <p>
            A &lt;relative-size&gt; keyword is interpreted relative to
            the table of font sizes and the font size of the parent
            element. Possible values are:<br/>[ larger | smaller
            ]<br/>For example, if the parent element has a font size
            of "medium", a value of "larger" will make the font size
            of the current element be "large". If the parent element's
            size is not close to a table entry, the <strong>user
              agent</strong> is free to interpolate between table
            entries or round off to the closest one. The <strong>user
              agent</strong> may have to extrapolate table values if the
            numerical value goes beyond the keywords.
          </p>
        </section>
        <section>
          <title>&lt;length&gt;</title>
          <p>
            A length value specifies an absolute font size (that is
            independent of the <strong>user agent</strong>'s font
            table).
          </p>
        </section>
      </section>
      <section>
        <title>7.8.8 "font-variant"</title>
        <section>
          <title>small-caps</title>
          <p>
            ... If a genuine small-caps font is not available,
            <strong>user agents</strong> should simulate a small-caps
            font...
          </p>
        </section>
      </section>
      <section>
        <title>7.8.9 "font-weight"</title>
        <section>
          <title>XSL modifications to the CSS definition:</title>
          <p>
            ... The association of other weights within a family to
            the numerical weight values is intended only to preserve
            the ordering of weights within that family. <strong>User
              agents</strong> must map names to values in a way that
            preserves visual order; a face mapped to a value must not
            be lighter than faces mapped to lower values. There is no
            guarantee on how a <strong>user agent</strong> will map
            fonts within a family to weight values. However, the
            following heuristics...
          </p>
        </section>
      </section>
      <section>
        <title>7.13.1 "alignment-adjust"</title>
        <section>
          <title>auto</title>
          <p>
            ... If the baseline-identifier does not exist in the
            baseline-table for the glyph or other inline-area, then
            the <strong>User Agent</strong> may either use heuristics
            to determine where that missing baseline would be or may
            use the dominant-baseline as a fallback.
          </p>
        </section>
      </section>
      <section>
        <title>7.13.3 "baseline-shift"</title>
        <section>
          <title>sub/super</title>
          <p>
            ... Because in most fonts the subscript position is
            normally given relative to the "alphabetic" baseline, the
            <strong>User Agent</strong> may compute the effective
            position for sub/superscripts <em>[sub: spec typo!]</em>
            when some other baseline is dominant. ... If there is no
            applicable font data the <strong>User Agent</strong> may
            use heuristics to determine the offset.
          </p>
        </section>
      </section>
      <section>
        <title>7.13.5 "dominant-baseline"</title>
        <p>
          ... If there is no baseline-table in the nominal font or if
          the baseline-table lacks an entry for the desired baseline,
          then the <strong>User Agent</strong> may use heuristics to
          determine the position of the desired baseline.
        </p>
      </section>
      <section>
        <title>7.14.11 "scaling-method"</title>
        <section>
          <title>auto</title>
          <p>
            The <strong>User Agent</strong> is free to choose either
            resampling, integer scaling, or any other scaling method.
          </p>
        </section>
        <section>
          <title>integer-pixels</title>
          <p>
            The <strong>User Agent</strong> should scale the image
            such that each pixel in the original image is scaled to
            the nearest integer number of device-pixels that yields an
            image less-then-or-equal-to the image size derived from
            the content-height, content-width, and scaling properties.
          </p>
        </section>
        <section>
          <title>resample-any-method</title>
          <p>
            The <strong>User Agent</strong> should resample the
            supplied image to provide an image that fills the size
            derived from the content-height, content-width, and
            scaling properties. The <strong>user agent</strong> may
            use any sampling method.
          </p>
        </section>
        <p>
          ... This is defined as a preference to allow the
          <strong>user agent</strong> the flexibility to adapt to
          device limitations and to accommodate over-constrained
          situations involving min/max dimensions and scale factors.
        </p>
      </section>
      <section>
        <title>7.14.12 "width"</title>
        <p>
          ... The width of a replaced element's box is intrinsic and
          may be scaled by the <strong>user agent </strong> if the
          value of this property is different than 'auto'.
        </p>
      </section>
      <section>
        <title>7.15.4 "line-height"</title>
        <section>
          <title>normal</title>
          <p>
            Tells <strong>user agents</strong> to set the computed
            value to a "reasonable" value based on the font size of
            the element.
          </p>
        </section>
        <p>
          ... When an element contains text that is rendered in more
          than one font, <strong>user agents</strong> should determine
          the "line-height" value according to the largest font size.
        </p>
      </section>
      <section>
        <title>7.15.9 "text-align"</title>
        <p>
          ... The actual justification algorithm used is <strong>user
            agent</strong> and written language dependent.<br/>
          Conforming <strong>user agents</strong> may interpret the
          value 'justify' as 'left' or 'right', depending on whether
          the element's default writing direction is left-to-right or
          right-to-left, respectively.
        </p>
      </section>
      <section>
        <title>7.15.11 "text-indent"</title>
        <p>
          ... <strong>User agents</strong> should render this
          indentation as blank space.
        </p>
      </section>
      <section>
        <title>7.16.2 "letter-spacing"</title>
        <section>
          <title>normal</title>
          <p>
            The spacing is the normal spacing for the current
            font. This value allows the <strong>user agent</strong> to
            alter the space between characters in order to justify
            text.
          </p>
        </section>
        <section>
          <title>&lt;length&gt;</title>
          <p>
            This value indicates inter-character space in addition to
            the default space between characters. Values may be
            negative, but there may be implementation-specific
            limits. <strong>User agents</strong> may not further
            increase or decrease the inter-character space in order to
            justify text.
          </p>
        </section>
        <p>
          Character-spacing algorithms are <strong>user agent</strong>
          dependent. Character spacing may also be influenced by
          justification (see the "text-align" property).<br/> When the
          resultant space between two characters is not the same as
          the default space, <strong>user agents</strong> should not
          use ligatures.<br/> Conforming <strong>user agents</strong>
          may consider the value of the 'letter-spacing' property to
          be 'normal'.
        </p>
        <section>
          <title>XSL modifications to the CSS definition:</title>
          <p>
            ...  For "normal": .optimum = "the normal spacing for the
            current font" / 2, .maximum = auto, .minimum = auto,
            .precedence = force, and .conditionality = discard. A
            value of auto for a component implies that the limits are
            <strong>User Agent</strong> specific.
          </p>
          <p>
            ... The CSS statement that "Conforming <strong>user
              agents</strong> may consider the value of the
            'letter-spacing' property to be 'normal'." does not apply
            in XSL, if the <strong>User Agent</strong> implements the
            "Extended" property set.
          </p>
          <p>
            ... The algorithm for resolving the adjusted values
            between word spacing and letter spacing is <strong>User
              Agent</strong> dependent.
          </p>
        </section>
      </section>
      <section>
        <title>7.16.4 "text-decoration"</title>
        <p>
          ... If the element has no content or no text content (e.g.,
          the IMG element in HTML), <strong>user agents</strong> must
          ignore this property.
        </p>
        <section>
          <title>blink</title>
          <p>
            ...  Conforming <strong>user agents</strong> are not
            required to support this value.
          </p>
        </section>
      </section>
      <section>
        <title>7.16.6 "text-transform"</title>
        <p>
          ... Conforming <strong>user agents</strong> may consider the
          value of "text-transform" to be "none" for characters that
          are not from the ISO Latin-1 repertoire and for elements in
          languages for which the transformation is different from
          that specified by the case-conversion tables of Unicode or
          ISO 10646.
        </p>
      </section>
      <section>
        <title>7.16.8 "word-spacing"</title>
        <p>
          ... Word spacing algorithms are <strong>user
            agent</strong>-dependent.
        </p>
        <section>
          <title>XSL modifications to the CSS definition:</title>
          <p>
            ... The algorithm for resolving the adjusted values
            between word spacing and letter spacing is <strong>User
              Agent</strong> dependent.
          </p>
        </section>
      </section>
      <section>
        <title>7.17.1 "color"</title>
        <p>Initial: depends on <strong>user agent</strong></p>
      </section>
      <section>
        <title>7.17.3 "rendering-intent"</title>
        <section>
          <title>auto</title>
          <p>
            This is the default behavior. The <strong>User
              Agent</strong> determines the best intent based on the
            content type. For image content containing an embedded
            profile, it shall be assumed that the intent specified
            within the profile is the desired intent. Otherwise, the
            <strong>user agent</strong> shall use the current profile
            and force the intent, overriding any intent that might be
            stored in the profile itself.
          </p>
        </section>
      </section>
      <section>
        <title>7.20.2 "overflow"</title>
        <section>
          <title>scroll</title>
          <p>
            This value indicates that the content is clipped and that
            if the <strong>user agent</strong> uses a scrolling
            mechanism that is visible on the screen (such as a scroll
            bar or a panner), that mechanism should be displayed for a
            box whether or not any of its content is clipped.
          </p>
        </section>
        <section>
          <title>auto</title>
          <p>
            The behavior of the "auto" value is <strong>user
              agent</strong> dependent, but should cause a scrolling
            mechanism to be provided for overflowing boxes.
          </p>
        </section>
      </section>
      <section>
        <title>7.21.2 "leader-pattern"</title>
        <section>
          <title>dots</title>
          <p>
            ... The choice of dot character is dependent on the
            <strong>user agent</strong>.
          </p>
        </section>
      </section>
      <section>
        <title>7.21.4 "leader-length"</title>
        <p>
          ... <strong>User agents</strong> may choose to use the value
          of "leader-length.optimum" to determine where to break the
          line, then use the minimum and maximum values during line
          justification.
        </p>
      </section>
      <section>
        <title>7.25.11 "media-usage"</title>
        <section>
          <title>auto</title>
          <p>
            The <strong>User Agent</strong> determines which value of
            "media-usage" (other than the "auto" value) is used. The
            <strong>User Agent</strong> may consider the type of media
            on which the presentation is to be placed in making this
            determination.<br/> NOTE:<br/> For example, the
            <strong>User Agent </strong> could use the following
            decision process. If the media is not continuous and is of
            fixed bounded size, then the "paginate" (described below)
            is used. Otherwise, the "bounded-in-one-dimension" is
            used.
          </p>
        </section>
        <section>
          <title>bounded-in-one-dimension</title>
          <p>
            ... It is an error if more or less than one of
            "page-height" or "page-width" is specified on the first
            page master that is used. The <strong>User Agent</strong>
            may recover as follows:...
          </p>
        </section>
        <section>
          <title>unbounded</title>
          <p>
            Only one page is generated per fo:page-sequence descendant
            from the fo:root. Neither "page-height" nor "page-width"
            may be specified on any page master that is used. If a
            value is specified for either property, it is an error and
            a <strong>User Agent</strong> may recover by ignoring the
            specified value. ...
          </p>
        </section>
      </section>
      <section>
        <title>7.25.13 "page-height"</title>
        <section>
          <title>auto</title>
          <p>
            The "page-height" shall be determined, in the case of
            continuous media, from the size of the <strong>User
              Agent</strong> window...
          </p>
        </section>
        <section>
          <title>NOTE:</title>
          <p>
            A <strong>User Agent</strong> may provide a way to declare
            the media for which formatting is to be done. This may be
            different from the media on which the formatted result is
            viewed. For example, a browser <strong>User Agent</strong>
            may be used to preview pages that are formatted for sheet
            media. In that case, the size calculation is based on the
            media for which formatting is done rather than the media
            being currently used.
          </p>
        </section>
      </section>
      <section>
        <title>7.25.15 "page-width"</title>
        <section>
          <title>auto</title>
          <p>
            The "page-width" shall be determined, in the case of
            continuous media, from the size of the <strong>User
              Agent</strong> window...
          </p>
        </section>
      </section>
      <section>
        <title>7.26.5 "border-separation"</title>
        <section>
          <title>&lt;length-bp-ip-direction&gt;</title>
          <p>
            ... Rows, columns, row groups, and column groups cannot
            have borders (i.e., <strong>user agents</strong> must
            ignore the border properties for those elements).
          </p>
        </section>
      </section>
      <section>
        <title>7.26.7 "caption-side"</title>
        <p>
          ... For a caption that is on the left or right side of a
          table box, on the other hand, a value other than "auto" for
          "width" sets the width explicitly, but "auto" tells the
          <strong>user agent</strong> to chose a "reasonable width".
        </p>
      </section>
      <section>
        <title>7.27.2 "glyph-orientation-horizontal"</title>
        <section>
          <title>&lt;angle&gt;</title>
          <p>
            ... The <strong>User Agent</strong> shall round the value
            of the angle to the closest of the permitted values.
          </p>
        </section>
      </section>
      <section>
        <title>7.27.3 "glyph-orientation-vertical"</title>
        <section>
          <title>auto</title>
          <p>
            ... The determination of which characters should be
            auto-rotated may vary across <strong>User Agents</strong>.
          </p>
        </section>
        <section>
          <title>&lt;angle&gt;</title>
          <p>
            ... The <strong>User Agent</strong> shall round the value
            of the angle to the closest of the permitted values.
          </p>
        </section>
      </section>
      <section>
        <title>7.27.6 "unicode-bidi"</title>
        <section>
          <title>XSL modifications to the CSS definition:</title>
          <p>
            ... Fallback:<br/> If it is not possible to present the
            characters in the correct order, then the
            <strong>UserAgent </strong> should display either a
            'missing character' glyph or display some indication that
            the content cannot be correctly rendered.
          </p>
        </section>
      </section>
      <section>
        <title>7.28.1 "content-type"</title>
        <p>
          ... This property specifies the content-type and may be used
          by a <strong>User Agent</strong> to select a rendering
          processor for the object.
        </p>
        <section>
          <title>auto</title>
          <p>
            No identification of the content-type. The <strong>User
              Agent</strong> may determine it by "sniffing" or by other
            means.
          </p>
        </section>
      </section>
      <section>
        <title>7.29.5 "border-color"</title>
        <p>
          ... If an element's border color is not specified with a
          "border" property, <strong>user agents</strong> must use the
          value of the element's "color" property as the computed
          value for the border color.
        </p>
      </section>
      <section>
        <title>7.29.9 "border-spacing"</title>
        <p>
          ... Rows, columns, row groups, and column groups cannot have
          borders (i.e., <strong>user agents</strong> must ignore the
          border properties for those elements).
        </p>
      </section>
      <section>
        <title>7.29.13 "font"</title>
        <p>
          ... If no font with the indicated characteristics exists on
          a given platform, the <strong>user agent</strong> should
          either intelligently substitute (e.g., a smaller version of
          the "caption" font might be used for the "small-caption"
          font), or substitute a <strong>user agent</strong> default
          font.
        </p>
      </section>
      <section>
        <title>7.29.19 "pause"</title>
        <p>Initial: depends on <strong>user agent</strong></p>
      </section>
      <section>
        <title>7.29.21 "size"</title>
        <p>
          ... Relative page boxes allow <strong>user agents</strong>
          to scale a document and make optimal use of the target size.
        </p>
        <p>
          ... <strong>User agents</strong> may allow users to control
          the transfer of the page box to the sheet (e.g., rotating an
          absolute page box that's being printed).
        </p>
        <ul>
          <li>
            Rendering page boxes that do not fit a target sheet<br/>
            If a page box does not fit the target sheet dimensions,
            the <strong>user agent</strong> may choose to:
            <ul>
              <li>
                Rotate the page box 90 degrees if this will make the
                page box fit.
              </li>
              <li>Scale the page to fit the target.</li>
            </ul>
            The <strong>user agent</strong> should consult the user
            before performing these operations.
          </li>
          <li>
            Positioning the page box on the sheet<br/> When the page
            box is smaller than the target size, the <strong>user
              agent</strong> is free to place the page box anywhere on
            the sheet.
          </li>
        </ul>
      </section>
      <section>
        <title>7.29.23 "white-space"</title>
        <section>
          <title>normal</title>
          <p>
            This value directs <strong>user agents</strong> to
            collapse sequences of whitespace, and break lines as
            necessary to fill line boxes. ...
          </p>
        </section>
        <section>
          <title>pre</title>
          <p>
            This value prevents <strong>user agents</strong> from
            collapsing sequences of whitespace. ...
          </p>
        </section>
        <p>
          ... Conforming <strong>user agents</strong> may ignore the
          'white-space' property in author and user style sheets but
          must specify a value for it in the default style sheet.
        </p>
      </section>
    </section>
  </body>
</document>