&gt; Hi, any update on this?<br><br>I was planning to submit a bug report, but hadn&#39;t because I don&#39;t have a reproduction recipe nor have I definitively pinned it down on Semantic.<br><br>Since I don&#39;t have a reproduction recipe, I haven&#39;t made much progress. I tried advising my after change hooks:<br>
<br>  (defadvice semantic-change-function (around my-advice-semantic-change-function activate)<br>    (let ((window-start-prior (window-start)))<br>      ad-do-it<br>      (my-msg &quot;DEBUG: During semantic-change-function, window-start change:%s,%s&quot; window-start-prior (window-start))))<br>
<br>Same defadvice for: c-after-change jit-lock-after-change. I also activated this advice for semantic-idle-core-handler. Basically this was to catch one of them in the act of scrolling the buffer. However, I encountered the bug with these in place and none showed a window-start discrepancy.<br>
<br>If you have a reliable reproduction recipe, that would be very helpful.<br><br>