[css-break] Clarify breaks between floats and adjacent content

Author: fantasai

css-break/Overview.html

@@ -841,8 +841,9 @@ <h3 id=possible-breaks><span class=secno>4.1. </span> Possible Break Points</h3>
      <dt>Block-parallel Fragmentation
 
      <dd> When the block flow direction of the siblings' containing block is
-      parallel to that of the fragmentation context: block-level boxes, table
-      row group boxes, table row boxes, multi-column column row boxes.
+      parallel to that of the fragmentation context: in-flow block-level
+      boxes, a float and an immediately-adjacent in-flow or floated box,
+      table row group boxes, table row boxes, multi-column column row boxes.
 
      <dt>Block-perpendicular Fragmentation
 

css-break/Overview.src.html

@@ -563,7 +563,8 @@ <h3 id="possible-breaks">
         <dd>
           When the block flow direction of the siblings' containing block
           is parallel to that of the fragmentation context:
-          block-level boxes,
+          in-flow block-level boxes,
+          a float and an immediately-adjacent in-flow or floated box,
           table row group boxes,
           table row boxes,
           multi-column column row boxes.