[css-break] Fix page/fragmentainer confusion.

Author: fantasai

css-break/Overview.bs

@@ -1076,7 +1076,8 @@ Transforms, Positioning, and Pagination</h3>
     (The origin of an overflow-only fragment is determined
     as if that content were overflowing an empty box with zero margins/borders/padding
     at the start of the fragmentainer.)
-    However, the separation and transfer of page boxes <em>should</em> occur last;
+    However, in order to reduce dataloss when printing,
+    the separation and transfer of page boxes <em>should</em> occur last;
     thus a transformed fragment that spans pages <em>should</em>
     be sliced at the page breaks and print in its entirety
     rather than being clipped by its originating page.
@@ -1093,11 +1094,13 @@ Transforms, Positioning, and Pagination</h3>
   <p>
     Absolute positioning affects layout and thus interacts with fragmentation.
     Both the coordinate system and absolutely-positioned boxes belonging to a containing block
-    will fragment across pages in the same fragmentation flow as the containing block.
+    will fragment across fragmentainers in the same fragmentation flow as the containing block.
 
   <p>
     UAs are not required to correctly position boxes that span a <i>fragmentation break</i>
     and whose <i>block-start</i> edge position depends on where the box's content fragments.
+  
+  <p>
     UAs with memory constraints that prevent them from manipulating an entire document in memory
     are not required to correctly position absolutely-positioned elements
     that end up on a previously-rendered page.