Bug 140777

Version:            (using KDE Devel)
Installed from:    Compiled sources

This bug is reported against KDE 3.5.6 (which cannot be selected from the list at the time of this writing).

Since KDE 3.5.6, khtml immediately marks links as visited when another page is loaded.

However, this leads to a considerable slowdown of page loading times (and accompanying bugs like bug 140768) especially noticeable on older hardware.

The problem is an unconditional style recalculation and full repaint *as soon as a new history entry is created*. Both operations need a very long time (compared to incremental painting operations) to complete to such an extent that they become user-noticeable.

A temporary fix is to apply this patch which basically reverts the functionality:

Index: html/html_documentimpl.cpp
===================================================================
--- html/html_documentimpl.cpp  (Revision 627229)
+++ html/html_documentimpl.cpp  (Arbeitskopie)
@@ -222,7 +222,7 @@

 void HTMLDocumentImpl::slotHistoryChanged()
 {
-    if ( !m_render )
+    if ( true || !m_render )
         return;

     recalcStyle( Force );


See also https://bugzilla.mozilla.org/show_bug.cgi?id=78510
on how Mozilla tackled this problem and which different solutions they pointed out.

I suggest reverting r617941 and implementing the 95% case for now (i. e. mark the link and only that link as being visited as soon as it has been activated). This incurs a relayout of the anchor element only which usually boils down to a repaint only (as long as color or text-decoration is changed only).

A proper fix must never do a full relayout+repaint, but issue repaints on the individual anchor elements only.