Avoid narrow boxes when using \width as box width unit

When the box has a special width, one should not consider that as a fixed width. Otherwise, due to implementation quirks, the width will be set on screen as 1 inch.

A better solution would be to actually set the width by taking in account the contents width, height ans total height. This is not very difficult, but I do not know whether it would workout well in the work area.

Fixes bug #10048.

src/insets/InsetBox.cpp

@@ -162,7 +162,7 @@ void InsetBox::setButtonLabel()
 
 bool InsetBox::hasFixedWidth() const
 {
-	return !params_.width.empty();
+	return !params_.width.empty() && params_.special == "none";
 }
 
 

status.21x

@@ -163,6 +163,8 @@ What's new
 - Fix warning about Undo when an empty subscript is automatically deleted in mathed
   (bug 10022).
 
+- Fix on screen narrow box when using \width as box width unit (bug 10048).
+
 * INTERNALS
 
 - Fix parsing problems of class and category declaration line in layout files